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The Basic Slippery Slope Argument

September 2015
Informal Logic Vol. 35(3):pp. 273–311.

DOI:10.22329/il.v35i3.4286

Authors:

University of Windsor

Although studies have yielded a detailed taxonomy of types of slippery slope arguments, they have failed to identify a basic argumentation scheme that applies to all. Therefore, there is no way of telling whether a given argument is a slippery slope argument or not. This paper solves the problem by providing a basic argumentation scheme. The scheme is shown to fit a clear and easily comprehensible example of a slippery slope argument that strongly appears to be reasonable, something that has also been lacking.

Modeling the Slippery Slope Argument in the Drug Example

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Slippery Descent of the Slippery Slope Argument

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The Sequence and the Gray Area

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Arguments in the Designer Babies Example

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Content uploaded by Douglas Walton

Content may be subject to copyright.

The Basic Slippery Slope Argument

DOUGLAS WALTON

Centre for Research in Reasoning, Argumentation and Rhetoric

Department of Philosophy

University of Windsor

Windsor, ON

Canada N9B 3P4

dwalton@uwindsor.ca

Abstract: Although studies have

yielded a detailed taxonomy of types

of slippery slope arguments, they

have failed to identify a basic argu-

mentation scheme that applies to all.

Therefore, there is no way of telling

whether a given argument is a slip-

pery slope argument or not. This

paper solves the problem by provid-

ing a basic argumentation scheme.

The scheme is shown to fit a clear

and easily comprehensible example

of a slippery slope argument that

strongly appears to be reasonable,

something that has also been lack-

ing.

Résumé: Bien que des études aient

donné une taxonomie détaillée des

types d'arguments de pente glissante,

ils n’ont pas réussi à identifier un

schème d’argumentation de base qui

s’applique à tous. Par conséquent, il

n'y a aucun moyen de savoir si un

argument donné est un argument de

la pente glissante ou non. Cet article

permet de résoudre ce problème par

un schème d'argumentation de base

qui correspond à un exemple clair et

facile à comprendre d’un argument

de pente glissante qui semble forte-

ment raisonnable, quelque chose

d’absent dans les études sur ces ar-

guments.

Keywords: vagueness, compressed slippery slope arguments, argumentation

schemes, genetics, eugenics, ethical argumentation, critical questioning

1. Introduction

The slippery slope argument has become a prominent and con-

troversial form of reasoning in biomedical ethics (van der Burg,

1991; Holtug, 1993; Launis, 2002; Saliger, 2007) and legal ar-

gumentation (Schauer, 1985; Volokh, 2002; Rizzo and Whit-

man, 2003). Notably since (Beardsley, 1966), it has been treated

as a distinctive type of argument in its own right in the logic

textbooks, typically under the heading of informal fallacies.

However, it remains a central problem that although different

definitions of the slippery slope argument as a distinctive type of

argument have been put forward in the literature, they don’t

agree with each other, and don’t go far enough to provide a pre-

Douglas Walton

274

cise model of the structure of the argument that is adequate to

move forward to solve the problem of how to analyze and eval-

uate slippery slope arguments. Corner et al. (2011, 134) noted

that while “it is simple to produce an intuitive characterization

of slippery slope arguments, they [these characterizations of

slippery slope arguments] have resisted attempts to provide a

comprehensive definition.” Is it this apparent intuitive simplicity

of slippery slope arguments that in fact makes them difficult to

define in a way that is clear, precise and comprehensive? The

definitions given in the literature identify some characteristics of

the slippery slope argument well enough, but do not include

enough characteristics to show precisely how they are combined

to make any of them workable as a comprehensive definition.

There has been considerable work done on analyzing many

interesting and controversial cases where the slippery slope ar-

gument has been used. This work has enabled the development

of a typology providing argumentation schemes for the analysis

and evaluation of different kinds of slippery slope arguments.

Corner et al. (2011, 134) noted that the definition of the slippery

slope argument in Walton (1992) distinguished four types of

slippery slope arguments, depending on the mechanism that

moves the argument forward: those based on causal mecha-

nisms, those that set precedents, those that are attributable to the

vagueness of concepts, and a fourth type that combines features

from each of the three other types. Corner et al. (2011, 134) note

however that although the Walton (1992) analysis provides a

detailed taxonomy, it fails to identify the core features common

to all slippery slope arguments, and therefore does not provide a

central definition that applies to all slippery slope arguments.

Lode (1999, 1492) has even gone so far as to claim that there is

no single, distinctive form of the slippery slope argument.

This paper provides an argumentation scheme for a basic

slippery slope argument that models the structure of this type of

argument and enables the construction of a definition that repre-

sents its core features. The slippery slope as a type of argument

is defined by stating ten requirements that need to be made for a

given argument to fit this category, and showing how the basic

scheme is related to its four subtypes and other closely related

types of arguments.

2. Sources of the slippery slope argument

Alfred Sidgwick is the earliest known author of a book on in-

formal logic, at least to my knowledge, to identify, illustrate and

The Basic Slippery Slope Argument

275

define the commonly used type of argument corresponding to

what is nowadays called the slippery slope argument. However,

Sidgwick (1910, 40) called it the thin edge of the wedge objec-

tion, defining it as follows.

We must not do this or that, it is often said, because if we

did we should be logically bound to do something else

which is plainly absurd or wrong. If we once begin to

take a certain course there is no knowing where we shall

be able to stop within any show of consistency; there

would be no reason for stopping anywhere in particular,

and we should be led on, step by step into action or opin-

ions that we all agree to call undesirable or untrue.

Later informal logic textbooks, notably including Beardsley

(1966, 176) took the direction of including the slippery slope

argument under the general heading of informal fallacies. How-

ever, although Beardsley described slippery slope arguments as

often alarming enough to be persuasive, he added the comment

(Beardsley, 4th ed., 1975, 150) that slippery slopes can be good

arguments in some instances. Currently the standard treatment

of the slippery slope argument in the logic textbooks is to in-

clude it under the section on fallacies, but also to occasionally

concede that such arguments are not always fallacious.1 But of

course, evaluating whether such an argument is fallacious de-

pends on how the type of argument is defined.

3. Structure of the slippery slope argument

Rizzo and Whitman (2003) cited three characteristics they claim

are common to all slippery slope arguments: (1) an initial, seem-

ingly acceptable decision, (2) a dangerous outcome that is unac-

ceptable, and (3) a process or mechanism leading from the initial

decision to the dangerous outcome. These three characteristics

surely are common to all slippery slope arguments, but until we

know more about the nature of the mechanism that leads from

the initial decision to the dangerous outcome, and how it works

1 A Google Ngram search for the expression ‘slippery slope fallacy’ on Au-

gust 12, 2014 found that there were zero occurrences in 1960, and although

the number went slightly upward by 1980, there was a tenfold increase peak-

ing in the 1990s. The search was not restricted to informal logic textbooks,

but covered all occurrences of the expression in all books in the Google data-

base at that time.

Douglas Walton

276

to drive the argumentation forward from the start point to the

end point, we have not comprehensively defined the slippery

slope type of argument. One problem is that it does not provide

a way of distinguishing between slippery slope arguments and

arguments from negative consequences, a much more common

form of argumentation.

Corner et al. (2011, 135) offer a better definition that states

that slippery slope arguments have four components: (1) an ini-

tial proposal for action, (2) an undesirable outcome, (3) a belief

that allowing the action will lead to a reevaluation of the unde-

sirable outcome in the future, and (4) the rejection of the initial

action proposed, based on this belief. This definition is more

comprehensive, because it brings out a fourth characteristic, but

it still fails to give a precise and sufficiently detailed account of

the mechanism through which allowing the initial action leads to

some sequence of actions or procedure that drives the sequence

forward from the start point to the end point. This fourth charac-

teristic is emphasized in the definition offered by Volokh (2002,

1030): “I think the most useful definition of a slippery slope is

one that covers all situations where decision A, which you might

find appealing, ends up materially increasing the probability that

others will bring about decision B, which you oppose.” Howev-

er, this definition is even more minimal than the previous two.

It is a problem cited by Walton (1992) that when students

first learn about slippery slope arguments, they tend to label any

argument from negative consequences as a slippery slope argu-

ment. This kind of labeling or (mislabeling) can have the effect

of shifting the burden of proof against the arguer who appears to

have committed a fallacy, and is therefore obliged to somehow

try to respond. Volokh (2002, 1030) has noted this reaction.

When someone says “I oppose partial-birth abortion bans

because they might lead to broader abortion restrictions,”

or “I oppose gun registration because it might lead to gun

prohibition,” the common reaction is “That’s a slippery

slope argument.”

A problem with this reaction is that in the absence of a precise

definition of the slippery slope argument, it is unclear whether

the two arguments cited are merely argument from negative

consequences. But the mere labeling of the argument as a slip-

pery slope may put the other side on the defensive.

Corner et al. (2011, 135) do distinguish between slippery

slope arguments and arguments from negative consequences.

They call argument from negative consequences “general con-

The Basic Slippery Slope Argument

277

sequentialist arguments,” citing the example of opposing the le-

galization of cannabis because it would lead to an increase in

chronic obstructive lung disease. In contrast they cited an exam-

ple of what they consider a genuine slippery slope argument: if

cannabis were legalized, attitudes towards harder drugs might

become more positive, and in the future heroin might also be-

come legalized. According to Saliger (2007, 342), “slippery

slope arguments belong to the class of practical consequence

arguments,” agreeing with the view of Corner et al. (2011) that

there is a distinction to be drawn between the two types of ar-

guments, one being a subset or special subtype of the other. On

Saliger’s view, (2007, 343), not all result arguments (arguments

from consequences) are slippery slope arguments. Drawing this

distinction is very helpful to working towards an adequate defi-

nition of the slippery slope argument, but by itself, none of these

definitions provides a precise enough or fully adequate compre-

hensive account of the slippery slope argument to explain how

the mechanism from the start point to the end point works, and

what its requirements are as a distinctive type of argument.

Holtug (1993, 403) defines the slippery slope argument as

having the following kind of structure as an argument with three

premises and conclusion.

Premise 1: An agent is considering whether or not to

bring about an action or class of actions A.

Premise 2: The argument is brought forward that if A is

carried out, another action B will inevitably or proba-

bly follow.

Premise 3: B is morally undesirable

Conclusion: The agent ought to refrain from bringing

about A.

He adds “Normally, B is not thought to follow directly from A,

but through a series of steps A1-An.” This definition is better but

still not fully adequate, because the mechanisms of how the

slope is slippery and how the sequence is driven forward by loss

of control are not accounted for.

4. Relation to vagueness and argument from negative

consequences

As shown in section 3, there has been a difficulty in clearly dis-

tinguishing between the slippery slope type of argument and

other kinds of arguments it is closely related to. This difficulty

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278

has been compounded by mixing the slippery slope argument

with another type of argument recognized in some of the texts

called the argument of the beard (Walton, 1996). The argument

of the beard is a criticism used by one party to attack an oppo-

nent by alleging that the opponent’s argument is fallacious be-

cause the opponent used a vague term falling on a continuum.

The first of the nine textbooks that included a discussion of this

fallacy between 1930 and 1967 was that of Thouless (1930).

Thouless (1930, 183) described it as the fallacy of arguing that

there is no difference between two things because there is a con-

tinuum between them that exhibits no sharp dividing line.

Damer (1980, 37) described it as the fallacy of arguing that it is

impossible or arbitrary to make a definite distinction between

two things on a continuum because there is no precise point on

the continuum where a distinction can be drawn between the one

thing and the other. This kind of argument is at least in some

cases fallacious because, as we now know, natural language ar-

gumentation, such as the kind of argumentation that takes place

in legal contexts, is open-textured. This means that a given term,

even if precisely defined, will always be open to vagueness and

reinterpretation when applied to a new case it has not yet been

tested against. Vagueness is a common phenomenon in the using

of a verbal criterion to draw classifications that are required in

argumentation. But vagueness is not always incorrect or falla-

cious in arguments, and is not always eliminable (Walton, 1996,

256).

The argument of the beard is very closely related to the so-

rites type of argument widely known to the ancient Greek phi-

losophers. A paradox called the heap (sorites) has been attribut-

ed to Eubulides, a student of Euclides, an older contemporary of

Plato. The paradox of the heap can be posed in the form of an

argument with two premises leading to an absurd conclusion

(Kneale and Kneale, 1962, 114).

Premise 1: If you take one grain away from a heap, it

makes no significant difference—you still have a

heap.

Premise 2: Each time you repeat this step, it makes no

difference, because one grain is too small to make a

difference between something being a heap or not.

Conclusion: Repeated long enough, the conclusion of this

reasoning will become absurd, for it will become ob-

vious that what is left can no longer be described as a

heap.

The Basic Slippery Slope Argument

279

This form of argument is different from the kind of slippery

slope argument we are familiar with in the logic textbooks be-

cause it is not about a sequence of actions that leads to some

dangerous outcome were a warning is being offered not to take

the first step in the sequence. However, we can see that there are

some similarities. Both forms of argument are about a sequence.

In both cases, once the sequence moves forward and is not

stopped, the result is a problematic outcome.

A comparable example of the sorites argument was called the

bald man paradox, described by the following sequence of ques-

tions and replies (Kneale and Kneale, 1962, 114).

Would you say that a man was bald if he had only one hair?

Yes.

Would you say that a man was bald if he had only two

hairs?

Yes.

Would you . . . , etc.

Then where do you draw the line?

This is a paradox, but putting it in this format shows that it could

also be used as the basis for a clever argument to attack some-

one who is having difficulty drawing the line, or making a clear-

cut line of demarcation on a continuum.

Cicero (Academica 93, H. Rackham, tr., Loeb Library, 1951,

586) understood that such paradoxes arise from vagueness be-

cause there is no clear cutoff point. If we are asked by gradual

stages whether a person is a rich man or a poor man we do not

know at what point in the addition or subtraction to give a defi-

nite answer. In such cases, since there is no way of setting abso-

lute limits, a series of questions asked in gradual stages can be

used to press ahead. So for example, 1,000,000 grains of sand is

a heap of sand, and a heap of sand minus one grain is still a

heap, but repeated actions of removing one grain at a time even-

tually forces you to accept the conclusion that one grain of sand

is a heap. Using such a clever argument to drive an opponent to

an absurd conclusion is a sophistical strategy that could perhaps

be associated with fallacies.

As we will see, once we have looked at a clear example of

the slippery slope argument and analyzed its components and

structure in detail in section 7, it will become evident how

vagueness is an essential component in the slippery slope argu-

ment. But at the same time it will become evident that vague-

ness is not the whole story of the slippery slope argument. There

are two factors that are combined to make a slippery slope ar-

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280

gument slippery, as will be shown in section 8. The first is the

connection between a so-called gray area caused by indetermi-

nacy, typically arising from vagueness, on a continuum in a con-

templated sequence of actions. The second factor is loss of con-

trol combined with this indeterminacy. Once the agent contem-

plating taking the first step in the sequence proceeds along the

sequence and enters the indeterminate gray area, it loses control

over its capability to stop moving ahead. The ultimate outcome

of the combination of these two factors is held by the slippery

slope arguer to result in the series of steps in the sequence lead-

ing to a catastrophic outcome.

Once the structure of the slippery slope argument has been

more clearly and precisely defined by the argumentation scheme

proposed in section 7, the distinction between it and the argu-

ment from negative consequences will become more evident.

All slippery slope arguments are instances of argument from

negative consequences, but they are special instances that have

the feature of the sequence of actions leading into and out of the

gray zone. To make the distinction between the two types of ar-

guments more precise for those who have to identify instances

of each of them in texts of natural language discourse, the char-

acteristics of argument from negative consequences have to be

defined more precisely.

Argument from negative consequences cites the consequenc-

es of a proposed course of action as a reason against taking that

course of action. This type of argument also has a positive form,

in which positive consequences of an action are cited as a reason

for carrying it out. The following are the two basic argumenta-

tion schemes for arguments from consequences (Walton, Reed

and Macagno, 2008, 332), where A represents a state that could

be brought about by an agent.

The first scheme is called argument from positive conse-

quences.

Premise: If A is brought about, good consequences will

plausibly occur.

Conclusion: Therefore A should be brought about.

The other scheme of the pair is called argument from negative

consequences.

Premise: If A is brought about, then bad consequences

will occur.

Conclusion: Therefore A should not be brought about.

The Basic Slippery Slope Argument

281

Argumentation from consequences offers a reason to accept a

proposal for action tentatively, subject to exceptions that may

arise as new circumstances become known. An instance of ar-

gument from consequences can be stronger or weaker, depend-

ing on its initial plausibility and the critical questions that have

been used to attack it.

Nobody would be likely to challenge the view that argument

from negative consequences is a legitimate and reasonable form

of argument in many instances, even though it can go wrong and

is associated with incorrect or fallacious arguments in some in-

stances. We use this kind of argument all the time, for example

when we consider whether or not to take a medication and look

on the bottle to see its listed side effects.

5. Compressed slippery slope arguments

In many examples that are identifiable as slippery slope argu-

ments, the argument is presented in a compressed form that

jumps to the conclusion seeming in one quick step. Consider the

following three examples of slippery slope arguments studied by

Corner, Hahn and Oaksford (2011, 133).

1. If we allow gay marriage, then in the future people will

want to marry their pets.

2. If voluntary euthanasia is legalized, then in the future

there will be more cases of medical murder.

3. If we accept voluntary ID cards in the UK, we will end

up with compulsory ID cards in the future.

Corner, Hahn and Oaksford (2011, 133), comment on the first

example that few would agree that homosexual marriages are

the beginning of the slippery slope to interspecies marriages, but

add that this argument was actually put forward by a group

called the American Family Research Council in 2004. On the

second example they comment that this argument is somewhat

more plausible. On the third example they comment that it

seems extremely likely that ID cards would become compulsory

if they were introduced in the UK. So here we have a range of

slippery slope arguments in which some are more plausible than

others.

In all three of these cases, it is hard to decide for sure on the

basis of the given evidence whether they are really slippery

slope arguments or should better be classified as simply argu-

ments from negative consequences. In the case of the third one,

Douglas Walton

282

it is not even really certain whether it is an argument. On the

surface it looks to be merely a prediction in the form of a condi-

tional statement. To reconstruct it as an argument we have to do

a lot of filling in and making assumptions with very little textual

evidence to go on. It looks like it is a slippery slope argument on

the basis that it is claiming that ending up with compulsory ID

cards in the future might be perceived to be a very dangerous

outcome, and that the first step in some sequence of events lead-

ing to this outcome is the acceptance of voluntary ID cards in

the UK. Some idea of how to make it into a slippery slope ar-

gument is given by Corner, Hahn and Oaksford (2011, 133) who

make the comment that it is likely that ID cards in the UK would

become compulsory if they were introduced if it turns out that

they were to function as an effective security measure. This out-

come might make them a necessity to guard against security

threats. However, it is not altogether certain whether this addi-

tional contextual information should be inserted as part of the

argument. This uncertainty poses a problem, because we do not

want to commit the straw man fallacy by inserting an implicit

premise in an argument that the arguer has not actually stated.

A special feature of these three examples is their compressed

format. We usually think of slippery slope arguments as built

around a connected sequence of actions and consequences start-

ing from an initial action or policy and then proceeding through

a sequence to an eventual outcome. However in many examples,

the three examples of slippery slope argument given above be-

ing cases in point, only the initial action and the eventual out-

come are specified.

On February 3, 2015, Britain became the first country to al-

low the creation of babies with genetic material from three per-

sons. Mitochondria, the powerhouses of our cells generate the

energy that our cells need to function properly. About 100 chil-

dren a year suffer from faults with mitochondria that are often

agonizing and fatal. Mitochondria contains DNA, and therefore

intervention using germline therapy results in genetic changes

that will be inherited by the mother’s children, and all their chil-

dren, and so forth. The slippery slope argument used against this

procedure is that it will be “the first step on the road to designer

babies” (No author given, Oh Baby, The Economist, February 7,

2015, page 12). The reply made to the slippery slope argument

given in the Economist article states: “[This complaint] is as

weak as any other slippery slope argument: approving one pro-

cedure does not mean automatically approving others.” Here we

have an instance of a condensed version of the slippery slope

The Basic Slippery Slope Argument

283

argument arguing against going ahead with this genetic inter-

vention. And then we have a counterargument claiming that the

slippery slope argument is weak because approving one proce-

dure does not mean automatically approving others.

In this case the slippery slope used to attack the argument for

genetic intervention does not seem to be inherently unreasona-

ble. The problem is that it is so compressed that we cannot tell

what the steps are supposed to be between this first step and the

alleged ultimate outcome of “designer babies,” taken by many to

be a catastrophic outcome because of its association with eugen-

ics. The term ‘eugenics’ is associated in the public mind with

the Nazi euthanasia program and other crimes aided by medical

policies in Nazi Germany (Bashford and Levine, 2010).

However the reply made to the slippery slope argument also

seems reasonable, because it makes the generally valid point

that approving one procedure does not automatically lead to ap-

proving others. In other words there it makes the reasonable

point that more evidence needs to be given by the proponent

showing how the intervening steps between the first step in the

catastrophic outcome are of such a nature that somewhere along

the line there is a descent into a set of circumstances where it is

no longer possible to go back and as a result the catastrophic

outcome becomes inevitable.

So in this instance, the argumentation between the two par-

ties is a stalemate, until the proponent replies to the respondent

by filling in enough gaps in the slippery slope sequence so that

the burden of proof shifts back again to the respondent side to

present further critical questions or counterarguments. The hy-

pothesis suggested by such cases is that in many instances of

slippery slope arguments some of the premises of an argument

are not stated explicitly, but are tacitly assumed. An enthyme-

matic argument is an argument that only makes sense if one or

more of its components (premises or conclusions) are inserted,

typically using Gricean implicature (Grice, 1975; Macagno and

Walton, 2013). Each case has to be analyzed and the arguments

in it classified using the textual evidence of the case. Here the

hypothesis is proposed that it is the presence of the second

through the sixth premises (in the argumentation scheme pre-

sented in section 7) that enables us to determine in any given

case whether the argument fits the scheme for the slippery slope

argument as well as fitting the more general scheme of argument

from negative consequences.

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284

6. The drug example

In this paper it is argued that slippery slope arguments can be

reasonable in some instances. Previous authors have maintained

this thesis (Govier, 1982; Walton, 1992). But as one looks

through the literature on slippery slope arguments, it is difficult

or even impossible to find a single example of one that meets all

the requirements for being a reasonable argument. Many of the

leading examples in the literature on euthanasia, freedom of

speech and so forth, are controversial and interesting, but ex-

pressed in such a compressed way, and mixed with other argu-

ments on a controversial issue that it is hard to figure out what

the premises and the conclusion are supposed to be. Another

problem is that the slippery slope is often supposed to be a falla-

cy, but it seems to be presupposed in the literature that under the

right conditions it can be a rational argument. On the other hand,

there is no clear example of it being a rational argument in the

literature, at least of a kind that can be used as a paradigm ex-

ample.

The closest example of an argument that looks to be simple

and a fairly reasonable instance of the slippery slope argument is

the following one quoted from (Burgess, 1993, 169).

Many slippery slope arguments in applied ethics are sim-

ple in structure, highly specific in scope and modest in

the practical counsel they offer us. A good example in-

volves the question whether to prescribe drug A or drug

B to a patient. For the condition concerned, A might

score best on almost all relevant criteria whilst B does

adequately on all, if less well on some. Suppose, further,

that there is no realistic possibility of switching drugs in

mid-treatment. Now, if A leads to tolerance, eventually

needing to be administered in a lethal dose, a simple and

sound slippery slope argument leads to the conclusion

that drug B is to be preferred.

This example compares arguments about the side effects of two

drugs. Each of the arguments is clearly an argument from nega-

tive consequences. The example is a good one because it is an

argument that seems quite reasonable. If it is not possible for the

patient to stop taking drug A in mid-treatment, and continuing to

take it will lead to the death of the patient at some point past

mid-treatment, the argument does seem to fit the slippery slope

category. Giving the patient advice not to start taking drug A

certainly does seem to be practical counsel given these circum-

The Basic Slippery Slope Argument

285

stances. Unfortunately however, the example is one of those

compressed instances of the argument where the sequence of

actions leading from the initial step to the eventual outcome is

not explicitly stated enough for us to grasp its essential features.

But still, the example has some good features, and it is possi-

ble to build on it by making up a hypothetical example about

taking drugs where the intervening sequence of actions has been

set out more explicitly. This example is easily recognizable as a

common sort of argument that appears to be a reasonable, even

if defeasible, argument. Let’s call it the drug example. This ex-

ample is set out in a narrative fashion in the following two para-

graphs.

Alice is a student. One day one of her fellow students who

had been taking heroin at a party offered Alice a free sample,

saying it would make her feel very good. Alice was hesitant be-

cause her father Bob had warned her never to take drugs because

they can be addictive and eventually lead to a situation where

they ruin your life entirely. Alice decides to think about the situ-

ation before accepting any offer of drugs. After that she told

Bob about what happened at the party. Bob repeated his earlier

advice to her, but was disturbed about the incident and thought

after some reflection that he should try to offer Alice a better

argument that would be more convincing to persuade her not to

take drugs such as heroin. He did a little research on addiction,

and presented a more carefully structured argument to her.

He told her that taking a drug of this kind is characterized by

immediate gratification but easily leads to a situation of depend-

ence because as it is taken again and again a dependency is cre-

ated where the body needs more and more of the drug in order to

get the same state of pleasure. This condition of tolerance to the

drug leads to withdrawal symptoms, such as intense cravings,

nausea, and tremors that can only be relieved by taking increas-

ingly larger amounts of it. At this point it can become extremely

difficult or impossible to stop taking drug, even with medical

intervention, even though continuing to take it can be cata-

strophic to health and normal function, even though it may lead

to serious medical disability or death. Based on these facts, Bob

reiterated that Alice should never take an addictive drug such as

heroin even one time because it is addictive, and once you start

taking it, even a few times, it becomes progressively harder to

stop, and you never know when it becomes so hard to stop that

you can’t do it. He argued that the long-term effects of such an

addiction on the body are ruinous to health and well-being. He

said that a sensible person knows that he or she should never

Douglas Walton

286

take such a drug, even once, because the risks are too great. He

also added some other arguments, including the argument that

taking heroin is illegal, and if anyone finds out you have taken

such a drug it can ruin your reputation.

In this case, Bob is giving advice to Alice as she makes a de-

cision about what choice to make when confronted by someone

offers her a drug such as heroin. His advice takes the form of an

argument, based on what Bob claims are some facts about addic-

tive substances. Bob’s argument seems fairly reasonable. Many

of us would even say that his argument is very reasonable and

that he is giving Alice some good advice.

On the other hand it might look to an audience that Bob’s

argumentation could be classified as a slippery slope argument.

Indeed Alice might reply to it by saying, “That’s a slippery

slope argument.” And since slippery slope arguments have tradi-

tionally been treated as fallacious, it might look to the audience,

at least initially, that there is something terribly wrong with this

argument.

7. A proposed argumentation scheme for the slippery slope

argument

Strictly speaking, to be a slippery slope, an argument has to

meet requirements of its argumentation scheme. The scheme has

a characteristic set of premises and a conclusion defined as

statement forms that contain variables and constants. The con-

stants have to be defined externally and restrictions are placed

on what entities can fit into the variables. There needs to be

identification rules that help a coder engaged in argument identi-

fication to determine whether a given argument in a natural lan-

guage text fits a particular scheme or not. There are also sets of

basic characteristics defining a particular type of argument such

as the slippery slope argument that can help to differentiate be-

tween instances of it and other comparable types of arguments.

There are six basic characteristics common to all slippery

slope arguments (Walton, 1992, 208). These six characteristics

are included in the ten basic characteristics listed below, but

have been reformulated in order to make them expressible with-

in the structure of a formal multi-agent deliberation dialogue.

There are two agents taking turns making moves in the form of

speech acts to each other. One kind of speech act is that of put-

ting forward an argument, another move made as a speech act is

that of replying to the argument by criticizing it for making an

The Basic Slippery Slope Argument

287

objection to it. In a deliberation dialogue, the agents taking part

in the proceedings are trying to arrive at a decision on what to

do in a particular set of circumstances, or perhaps to agree on a

policy. The participant contemplating carrying out the particular

action in the case of a slippery slope argument will be called the

agent. The responding party, who is criticizing the argument or

objecting to it by putting forward a slippery slope argument, will

be called the critic. For purposes of the ease of exposition, the

former agent will always be designated as “she,” and the other

agent will be designated as “he.”

Using this terminology, the ten basic characteristics of the

slippery slope type of argument can be formulated as follows.

1. The agent is deliberating on whether to take an action or

accept a policy.

2. The critic postulates a sequence of further actions that

will move forward as consequences of the agent’s car-

rying out the initial contemplated action.

3. At the beginning, each single step in the sequence ap-

pears to be a small or not very significant one, but as

the sequence proceeds the consequences tend to be-

come more serious.

4. There are factors that help to propel the argument and

series of consequences along the sequence, making it

progressively harder for the agent to resist continuing

to move ahead.

5. At the beginning of the sequence the agent retains con-

trol of whether to stop moving ahead.

6. However during some interval along the sequence of ac-

tions, the agent loses control of the possibility of stop-

ping from moving ahead.

7. This interval cannot be precisely specified, meaning that

the agent never knows during the earlier steps in the

sequence at what precise point her loss of control will

take place.

8. Once the agent enters into the interval where she loses

control, she cannot go back and must continue the pro-

cedure of bringing about further consequences in the

sequence.

9. Past the loss of control interval, the sequence inevitably

proceeds to an endpoint, an outcome that is catastrophic

for the agent, and for the other agents taking part in the

deliberation.

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288

10. The critic argues that the agent should not take the first

step, because if she does, she will be led to unpredicta-

bly lose control, and then will be unable to avoid the

catastrophic outcome.

These ten characteristics are codified in the basic argumenta-

tion scheme for the slippery slope argument below, a substan-

tially revised version of the comparable argumentation scheme

for the slippery slope argument formulated in (Walton, 1992,

199-200). Let’s call it the basic argumentation scheme for the

slippery slope argument.

Initial Premise: An agent α is considering carrying out an

action A0.

Sequential Premise: Carrying out A0 would lead to A1,

which would in turn lead to carrying out A2, and so

forth, through a sequence A2, . . . , Ax, . . . Ay, . . ., An.

Indeterminacy Premise: There is a sequence A0, A1, A2, . . .

, Ax, . . . Ay, . . ., An that contains a subsequence Ax, . . .

Ay called the gray zone where x and y are indeterminate

points.

Control Premise: α has control over whether to stop carry-

ing out the actions in the sequence until α reaches some

indeterminate point in the gray zone Ax, . . . Ay.

Loss of Control Premise: Once α reaches the indetermi-

nate point in the gray zone Ax, . . . Ay, α will lose con-

trol and will be compelled to keep carrying out actions

until she reaches An.

Catastrophic Outcome Premise: An is a catastrophic out-

come that should be avoided if possible.

Conclusion: A0 should not be brought about.

The factors referred to in characteristic 4 are called drivers. A

driver is a catalyst that helps to propel the argument along the

sequence and the argument, making it progressively harder for

the agent to resist continuing. There can be a driver such that

once the agent takes a given step Ai then she will also be natural-

ly, but not initially, inevitably impelled forward to take the next

step Aj of the sequence. There can be more than one driver in a

given slippery slope argument, and different drivers can come

into play at different parts of the sequence, as illustrated in the

drug example below. Drivers include such factors as precedent,

public acceptance, or vagueness, but can include many other

factors as well. In the full slippery slope argument previously

The Basic Slippery Slope Argument

289

modeled by (Walton, 1992, 199), the driver is a climate of social

opinion. To cite an example, public acceptance of voluntary eu-

thanasia may lead to wider public acceptance of the policy of

terminating life, which could lead to greater tolerance for poli-

cies of ending life other than on a voluntary basis. Or to cite an-

other kind of example of a driver, taking a drug could become

habit-forming and eventually lead to an addiction.

To show how Bob’s argument in the drug example fits the

scheme, it is necessary to identify the premises and the conclu-

sion of Bob’s argument. When this argument is fitted to the

scheme, there are seven premises, two drivers and one conclu-

sion. Below, each premise is given a name as a label.

Initial Premise: You are considering taking a drug, in this

instance heroin.

First Sequential Premise: One thing leads to another, and

so it is very likely that you will continue taking the

drug, and may suffer no visible harmful effects.

First Driver: Taking a drug such as heroin typically results

in immediate gratification that leads to forward to re-

peat this feeling of pleasure more than once.

Indeterminacy Premise: People vary concerning their sus-

ceptibility to a drug such as heroin. Some become ad-

dicted very easily while others can control it for a long

time.

Control Premise: At first you have control over whether to

stop taking the drug at any point.

Loss of Control Premise: Once you have become addicted,

you have lost control, and you cannot stop taking the

drug.

Second Driver: Once the body has adjusted to the drug,

and has become dependent on it, withdrawal symptoms

make it very hard to reduce or discontinue taking the

drug.

Second Sequential Premise: Once you have lost control,

you are impelled forward to the catastrophic outcome,

such as losing your family, your friends, your career,

your financial assets, your reputation and your health,

or even your life.2

2 This sequence should not be seen as inevitable. There are exceptions. For

example, you are impelled to the final outcome unless you can get medical

help. But even if you can get medical help, the addiction may be too strong.

Douglas Walton

290

Catastrophic Outcome Premise: This outcome is cata-

strophic and should be avoided at all costs.

Conclusion: You should not take this drug.

The problem posed by this example is how to model the drivers.

It seems that the drivers should be additional premises, but they

are optional, meaning that in some cases no drivers are identi-

fied while in other cases one or more drivers can be identified.

This example suggests that the drivers can be modeled as addi-

tional premises that support particular premises of the kind stat-

ed explicitly in the basic argumentation scheme for the slippery

slope argument. Following this method, the first driver is taken

as a premise that supports the first sequential premise, while the

second driver is taken as an additional premise that supports the

loss of control premise. This way of modeling the drivers in the

example is shown in figure 1. It follows the format of the Car-

neades Argumentation System (CAS) by showing the ultimate

conclusion at the left, and using the lines going from the premis-

es to a circular argument node that goes to the conclusion (Gor-

don, 2010). A pro argument is represented by a plus symbol in

the argument node.

Figure 1: Modeling the Slippery Slope Argument

in the Drug Example

In figure 1 the scheme for the basic slippery slope argument

fits the node containing the notation +a1. It is an important re-

quirement for this scheme that the second through sixth premis-

es be present (either explicitly or implicitly). Without these

premises, the argument clearly is an instance of argument from

The Basic Slippery Slope Argument

291

negative consequences, but not one that can also be properly

classified as a slippery slope argument. In more compressed ver-

sions of the slippery slope argument, one or more of the six es-

sential premises are unstated but implicit. In this case we have

shown the sequential premise as split into two. This is not an

essential feature of slippery slope arguments but it is useful to

split them in some cases when showing drivers.

The broader structure of the slippery slope argument repre-

sented by this scheme has a modus tollens form comparable to

the form of argument known as reductio ad absurdum.

If the initial step A0 is taken (as can be seen by applying

the next six premises) the catastrophic outcome An will

occur, or at least will be likely to occur in the future.

The catastrophic outcome An should carefully be avoided.

Therefore the initial step A0 should not be taken.

It can also be seen that this broader structure of the argument is

a special instance of the scheme for argument from negative

consequences. These remarks suggest the beginning of a classi-

fication system. In this paper, the task of building a classifica-

tion system showing the connections between these related types

of argument is not attempted. But in the literature (Govier, 1982;

Walton, 1992), several types of slippery slope arguments have

been identified, such as the precedent type, the linguistic type

(based on vagueness of a term), and the causal type. Some re-

marks are needed how these types can be classified as special

instances of the basic argumentation scheme formulated above.

A scheme for the causal type of slippery slope is quoted from

(Walton, 1992, 93).

Initial Action Premise: S0 is up for consideration as a

proposal that seems initially like something which

should be brought about.

Causal Sequence Premise: Bringing about S0 would

plausibly cause (in the given circumstances, as far as

we know) S1, which would in turn plausibly cause S2,

and so forth, through the sequence S2, . . . , Sn (for

some finite n).

Ultimate Outcome Premise: Sn is not something which

should be brought about (because it is horrible, unde-

sirable, etc.).

Conclusion: S0 should not be brought about.

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292

How does this scheme fit the one for the basic slippery slope

argument? Several remarks are in order to address this question.

First there are some slight differences of syntax. The basic

scheme talks about carrying out actions while the causal scheme

talks about bringing about states of affairs. These differences

can be reconciled by treating an agent’s carrying out an action,

at least for the purposes of relating the two schemes, as being

comparable to an agent’s bringing about a state of affairs. This

is a tricky point, because it requires some considerations in the

philosophy of action, but there is no space for that here. But it is

not the main problem.

The main problem is that the causal scheme explicitly uses

the term ‘cause’ in the causal sequence premise. So whenever

we try to define the controversial notion of cause, the causal

scheme is restricted to instances in which one step in the se-

quence causes the next step (Walton, Reed and Macagno, chap-

ter 3). The basic scheme is more general as it uses the language

of one action leading to another action, a language that could

include causal steps as well as non-causal steps in the sequence.

The basic scheme is general enough to encompass both kinds of

steps. Hence it seems reasonable to conclude that the causal

scheme can be classified as special subspecies of the more gen-

eral basic scheme.

Another problem is that the causal scheme as stated above,

only has three premises, whereas the basic scheme has six prem-

ises. What needs to be done to integrate the two schemes is to

revise the causal scheme by adding the three additional premises

of the kinds required by the basic scheme. So what needs to be

done is to revise the causal scheme of 1992 by adding these

three premises to it. By this means the Walton 1992 version

causal scheme can be shown to be a subscheme of the basic

slippery slope scheme. Basically the same kind of procedure of

revision can be used to accommodate the scheme for the prece-

dent slippery slope argument from (Walton, 1992, 155) and the

scheme for the full slippery slope argument (Walton, 1992,

199). This makes these earlier versions of these schemes more

complex, but it also brings out essential elements of the slippery

slope argument shown to be important in this paper.

It is important to realize that the basic slippery slope argu-

ment is a species of goal-based reasoning, so-called practical

reasoning, of which the conclusion can be not only a single ac-

tion but also a proposal or policy for action. The practical rea-

soning form of argument applies not only to actions by a single

agent but also to multi-agent deliberation in which a group of

The Basic Slippery Slope Argument

293

agents is collectively deciding on what to do in a given set of

circumstances. Both practical reasoning and the slippery slope

argument are based not only on goals but also on values that can

support or detract from such goals. Case in point is the designer

babies example from section 5. This argument was directed

against the practical wisdom of the decision made by British

MPs in 2015 to allow the creation of children with genetic mate-

rial from three people. The complaint made in the slippery slope

argument was that the decision made to approve this procedure

by agreeing that it should become policy is the first step on the

road to designer babies.

Argument from precedent is a form of argument that has its

own scheme (Walton, Reed and Macagno, 2008, 344), and it is

this scheme combined with the basic scheme that produces the

precedent slippery slope argument. This latter structure has been

built on a series of cases in the argumentation scheme for the

precedent slippery slope argument in (Walton, 1992, 155). Ac-

cording to this form of argument allowing an exception to a

general rule such as a law would lead to a sequence of other

precedents, cases that are similar, and that would ultimately lead

to an intolerable outcome. The following example from (Wal-

ton, 1992, 267-27) was about the burning of an American flag

by Gregory Lee Johnson during a political demonstration to pro-

test policies of the Reagan administration. Johnson was convict-

ed of desecration of a venerated object, but the Texas Appeals

Court overturned the ruling by arguing that Johnson’s act could

be classified as “expressive conduct” protected as free speech.

The Texas Court of Criminal Appeals argued that Johnson's

conduct was a form of “symbolic speech” intended to convey a

political message and that, as such, it should be protected by the

First Amendment, which includes, under the heading of

“speech,” such acts as organized demonstrations and the distri-

bution of literature. In the opinion written by Justice William J.

Brennan, Jr. in the case of Texas v. Johnson (1989 WL

65231(U.S.), 57 U.S.L.W. 4770), it was argued that Johnson’s

action can be classified as the expression of an idea, of a kind

protected by the First Amendment, quoted from (Walton, 1992,

269-270):

We perceive no basis on which to hold that the principle

underlying our decision in Schacht does not apply to this

case. To conclude that the Government may permit des-

ignated symbols to be used to communicate only a lim-

ited set of messages would be to enter territory having no

Douglas Walton

294

discernible or defensible boundaries. Could the Govern-

ment, on this theory, prohibit the burning of state flags?

Of copies of the Presidential seal? Of the Constitution?

In evaluating these choices under the First Amendment,

how would we decide which symbols were sufficiently

special to warrant this unique status? To do so, we would

be forced to consult our own political preferences, and

impose them on the citizenry, in the very way that the

First Amendment forbids us to do.

In (Walton, 1992, 270) this argument was classified as an in-

stance of the precedent type of slippery slope argument. It was

classified as a variant of the precedent slippery slope argument

where a first step is said to lead to a series of related decisions

about what to include. Justice Brennan argued that these subse-

quent decisions, as one precedent led to another, would culmi-

nate in a final outcome where the courts would be imposing

their own political preferences on all citizens, a violation of the

First Amendment. This outcome would appear to be catastrophic

enough in a free country to make the argument against it an in-

stance of the precedent slippery slope argument. In this case

there is a sequence of steps in which a legal decision based on

precedent is made at each step, and the sequence as a whole

leads to a catastrophic outcome.

Any decision made by the Supreme Court is a precedent that

takes priority over rulings of other courts, such as a state court,

and is binding on them. In the common law system, laws are

based on statutes passed by a legislative assembly, but statutory

interpretation is based on arguments put forward and decided by

the courts. Importantly, whether a law is held to be binding or

not in a given case depends on precedents set in similar prior

cases. One precedent leads to another as the same rule that held

up in one case is applied to another. This chain of argumentation

naturally falls into a sequence so that when one case is a prece-

dent for another, the second one can become a precedent for

third one, and so forth. An influential ruling by the Supreme

Court can easily set such a chain of sequential argumentation

into motion.

In this case the sequence of argumentation is impelled for-

ward by four drivers. The first one is its setting in the common

law system where decisions made on the basis argument from

precedent can be binding on other cases. The notion of a prece-

dent and the way it works in the common law system means that

a decision can set up a slippery slope argument to attack the pri-

or argument that an action should be taken to make a ruling that

The Basic Slippery Slope Argument

295

leads to the formulation of a new law or acceptance of a new

exception should be applied to a given case at issue. A precedent

drives an agent forward to the catastrophic outcome by a route

that is not causal, but logical. The second driver is that of com-

mitment. The proponent of the argument attacked by the slip-

pery slope argument must concede that if she accepts that the

defendant should be convicted of a crime in the present case she

must also concede, on pain of inconsistency, that another person

in a similar situation should also be convicted of the same crime.

The second driver in such a case is the commitment set in place

that makes an arguer logically bound to accept a similar proposi-

tion even though it is different in some respects from the one it

is being compared to. The third driver is the openness or so-

called open texture of terms and contexts used in legal argumen-

tation, such as “free speech,” that are continually subject to rein-

terpretation as new cases are decided in the courts. This linguis-

tic factor pertains to the vagueness, or open texture as it is often

called, of key legal terms. The fourth driver is the notion of sim-

ilarity that drives chains of argumentation based on interpreta-

tion forward in courts on the principle of treating similar cases

alike. This is to assume that argument from precedent is based

on argument from analogy.

The argumentation scheme for the precedent slippery slope

argument given in (Walton 1992, 155) begins with a premise

that the particular case at issue is claimed to be an exception to a

rule. The next premise, called the related cases premise, holds

that the case at issue is similar to another case, which in turn is

similar to a sequence of other cases, so that giving a ruling on

the original case, a chain of argumentation will be set up by case

to case similarity (argument from analogy). The third premise

says that treating the case at issue as an exception to a rule

would be intolerable because it would move this chain of argu-

mentation forward so that it would ultimately lead to a cata-

strophic or intolerable outcome. The conclusion of the argument

is that the original case cannot be judged to be an exception to

the rule. This form of argument fits into the basic scheme be-

cause it has all the same characteristics as those matching the

premises and conclusion as those specified in the basic scheme.

The difference is in the four drivers that can propel a ruling for-

ward from case to case.

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296

8. What makes the slope slippery?

The answer to the question of what makes the slippery slope ar-

gument slippery begins with the observation (Schauer, 1985,

378) that as one proceeds along a sequence of small steps, it is

impossible to know where to draw the line. One enters a gray

zone, but because of the indeterminacy of this gray zone, there is

no specific point along the sequence where it begins (Walton,

1992, 50-52). But at some undetermined point within this gray

zone, one has lost control, meaning that there is no longer the

possibility of turning back (Walton, 1974). After reaching that

point one is impelled down the remaining part of the slope to the

catastrophic outcome at the bottom.

From the drug example one can see the importance of the

possibility that there can be two or more drivers pushing the se-

quence of argumentation forward into the gray zone, through it

and beyond until the agent is on the steepening part of the slope

where it is impelled downward with no control toward the cata-

strophic outcome. The gray zone (gray area) within which con-

trol is lost is represented in figure 2.

Figure 2: Slippery Descent of the Slippery Slope Argument

On the part of the descent before reaching the gray zone and en-

tering into it, the agent’s actions are impelled forward by the

The Basic Slippery Slope Argument

297

pleasure of taking the drug. At some undefined point in the gray

zone the agent has become addicted to the drug and now it is

much more difficult to stop taking it, for some agents perhaps

even impossible, because of the increasingly painful withdrawal

symptoms. The paradox of the heap (bald man) is not itself a

slippery slope argument, but its feature of the gray area is the

key component that explains what makes the slippery slope

slippery. What makes it slippery, as shown precisely in the

scheme proposed in section 7, is the connection between the

gray area and the loss of control once one has entered into it.

Now we are in a position to obtain a much clearer grasp of

how the slippery slope argument, even though it is a species of

argument from negative consequences, is distinct as a special

form of argument in its own right with identifiable characteris-

tics that mark it out. The first characteristic is that the transition

from the action to its consequence must take place over an inter-

vening sequence of actions A0, A1, A2, ... , Ax, ... Ay, ... , An such

that each action in the sequence leads to the next one, even

though the individual links between pairs of actions can be quite

different. The second characteristic is that the sequence contains

a subsequence Ax, ... Ay called the gray zone where x and y are

indeterminate points. The third characteristic is that once the

sequence of actions enters the gray zone (area) the agent loses

control over whether to continue taking the actions in the se-

quence or not. The fourth characteristic is that once the sequence

of actions proceeds out of the gray zone, the agent has lost con-

trol, and is impelled if not inevitably drawn much more strongly,

to the end point of the sequence, the catastrophic outcome. The-

se four characteristics combine so that once the agent has taken

the first step A0, the slippery slope sequence will kick into place

and generate a movement of its own that will carry the agent

forward more and more strongly toward the catastrophic out-

come, causing the agent to lose control in an insidious manner.

The slippery slope argument does essentially involve vague-

ness on a continuum, but that is far from the whole story of it. A

vitally important component is the loss of control as the se-

quence of actions is moved forward by the drivers over the gray

area toward the ultimate outcome. Once the structure of the slip-

pery slope argument has been precisely modeled, and a reasona-

bly clear case, namely the drug example, is given to show how

such an argument can be reasonable in some instances, the force

and legitimacy of the argument can be appreciated. The essential

structure of the slippery slope argument is shown in figure 3.

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298

Figure 3: The Sequence and the Gray Area

The essential structure of the argument is the sequence of ac-

tions beginning with the first action A1, the moving forward of

the sequence through the gray area, loss of control at some point

as the sequence goes through the gray area, and the ultimate de-

scent to the catastrophic outcome An. What makes the slippery

slope slippery is the indeterminacy of the gray area, which

means that the point at which the agent loses control cannot be

anticipated in advance. The agent can rationalize, thinking that it

can stop at any point, and this is true at first, but insidiously be-

comes false in a way that is impossible to anticipate, and so the

agent becomes trapped. Once the slippery slope argument is ex-

plained in this way, it is easy to appreciate why it is a scary ar-

gument, and one that a rational agent should pay careful atten-

tion to. On the other hand, because it is such a scary argument, it

is also easy to take advantage of it to try to manipulate an audi-

ence with sleight-of-hand. There are always two sides to it. It

can be attacked as well as defended, and needs to be evaluated

on a balance of considerations where the pro and con arguments

are displayed together in an argumentation tree.

We can briefly illustrate how this procedure works by look-

ing back to the example of the designer babies slippery slope

argument from section 5. In figure 4, the action of approving the

procedure of genetic intervention is shown in the rectangle con-

taining “Approve Procedure.” The pro-argument supporting this

conclusion is labeled in the circle containing the notation +a1.

Below this argument there is a second argument, a con argument

labeled—a2, attacking the pro-argument +a1. Finally there is a

con argument—a3 attacking the argument—a2. The con argu-

ment is based on the premise stating that approving one proce-

dure does not mean automatically approving others. In the fig-

ure, this premise is indicated by the notation “Not Automatical-

ly.”

The Basic Slippery Slope Argument

299

Figure 4: Arguments in the Designer Babies Example

The conclusion of argument a1, the action of approving the pro-

cedure for transferring the nucleus of an egg cell with damaged

mitochondria into the body of an egg that is not damaged, is

shown in the rectangle at the top left of figure 4. The slippery

slope argument is shown in the figure at this argument a2. The

counterargument to the slippery slope argument is the argument

a3, which has the premise that approving one procedure does not

mean automatically approving others. So argument a1 is a pro-

argument supporting the ultimate conclusion. Argument a2 is a

con argument, a slippery slope argument attacking argument a1.

And argument a3 attacks argument a2. It is an instance of two

undercutters, where an undercutter is defined following Pollock

(1995) as an argument attacking the inferential link between the

premises and conclusion of a prior argument. This example is a

case of one undercutter undercutting another undercutter.

This argument, as shown in figure 4, is a classical example of

the formalism widely used in artificial intelligence called ab-

stract argumentation frameworks. In this formal model, argu-

ments can take on one of three values: accepted (in), rejected

(out), or neither accepted nor rejected. In this formalism, an ar-

gument is accepted (in) as long as it is not attacked by any other

argument that is accepted (in). But an argument is rejected (out)

if it is attacked by any other argument that is accepted (in). If the

first argument is attacked by a second argument that is accepted

(in) then the first argument is refuted (out). But if the second

argument is attacked by a third argument that is accepted (in) in

the second argument becomes unacceptable (out). Therefore, the

status of the first argument is automatically restored. It is

changed from unacceptable (out) to acceptable (in). Neverthe-

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300

less while this formalism does model some main aspects of the

slippery slope argument used in the designer babies example, it

can be improved significantly by adding the argumentation

scheme for the basic slippery slope argument into the structure

of the figure and taking this scheme into account.

Above it was noted that the slippery slope argument is shown

in figure 4 as argument a2. In some formal argumentation sys-

tems of the kind developed in artificial intelligence, such as AS-

PIC+ (Prakken 2010) and CAS (Gordon 2010). In CAS, for ex-

ample, the argumentation schemes, including the one for the

slippery slope argument that is contained in the computational

structure CAS, fit into the circular argument nodes. In this in-

stance, the argument node containing the notation a2 is taken to

be an instance of the slippery slope argument. This means that

the requirements of the scheme need to be built into the argu-

ment displayed at node a2. In such systems, a slippery slope ar-

gument is modeled in such a way that it does not successfully

refute the original argument it was directed against unless the

refuting argument fits the requirements of the scheme, in this

instance the basic scheme for the slippery slope argument. This

means that all the premises of the slippery slope argument

shown in the basic scheme have to fit the example, and the slope

argument is not adequate to refute the argument it was directed

against unless it can be shown that all the premises of the basic

scheme are present in the text, or if they are implicit they can be

made explicit using evidence from the text, in this case the ar-

gument as it was put forward in the Economist article. In this

instance the argument that this is the first step to designer babies

is meant to be a slippery slope argument, and is only possible if

taken this way, but nevertheless states only one of the premises

of the basic slippery slope scheme. No evidence indicating or

supporting the other premises is provided. Hence the slippery

argument fails in the designer babies example, judging by the

text given as the example.

The fundamental problem is that the model of the argumenta-

tion shown in figure 4 only has the first step and the conclusion

of the basic argumentation scheme for the slippery slope argu-

ment. None of the other premises has been explicitly stated. But

the argument cannot be evaluated as a slippery slope argument,

using the basic scheme to represent the logical form of that type

of argument, until the other implicit premises have been made

explicit. Until this has been done, if the argument a2 in the de-

signer babies is supposed to be a slippery slope argument, the

counterargument a3 is basically correct to make the criticism

The Basic Slippery Slope Argument

301

that this prior argument is weak, because it does not show how

one step in the sequence automatically goes into a gray area

leading to loss of control, and ultimately to the allegedly cata-

strophic conclusion of approving a procedure that will produce

“designer babies.”

The example shows how an argumentation scheme can be

used within a formal argumentation model as a device for argu-

ment evaluation. An argument can be shown to be weak if it

omits or fails to substantiate some of the premises required by

the scheme. A more general discussion on how formal argumen-

tation are applicable to such cases is offered in section 10.

9. Critically questioning a slippery slope argument

The argumentation scheme for the slippery slope argument pre-

sented in (Walton 1992) has a list of critical questions attaching

to this scheme. Slippery slope arguments are defeasible, mean-

ing that they only hold tentatively, and may be defeated by the

asking of critical questions or the putting forward of counter ar-

guments. Once such an argument has been identified, the next

question is how to respond to it appropriately by examining its

pros and cons.

There are basically three ways to attack an argument in for-

mal argumentation systems such as ASPIC+ and CAS: you can

attack its premises, you can attack the inferential link between

premises and conclusion, or you can attack the conclusion di-

rectly by posing a counterargument against it, making the claim

that the conclusion is false, or not acceptable based on the evi-

dence. However, there are also other ways to attack an argument

that someone puts forward as a slippery slope argument. As

shown by the examples above, such an argument may not really

be a slippery slope argument, but maybe better fit some other

argumentation scheme such as argument from negative conse-

quences, without fitting the requirements necessary to make it a

genuine slippery slope argument. To attack the argument in this

way, the critic needs to bring forward the argumentation scheme

for the slippery slope argument, and also perhaps explain the

necessary characteristics that identify an argument as fitting the

slippery slope category, and show that the given argument fails

to meet one or more of these requirements. This move shifts the

burden of proof onto the proponent of the argument to bring

forward more evidence to show that it fits the slippery slope cat-

egory. Failure to meet these requirements means that the argu-

Douglas Walton

302

ment cannot be criticized as a fallacious slippery slope argu-

ment.

Another way to attack the slippery slope argument is to ask

critical questions matching the argumentation scheme (Walton,

1992). These critical questions represent standard ways of find-

ing gaps in the argument and probing into its weak points. They

are therefore helpful to the beginner who has not been trained in

argumentation and may find it difficult to respond to a cleverly

expressed slippery slope argument, even though the argument is

in such a compressed form that is full of all kinds of holes. One

of the most important critical questions is whether there is a

bright line that can be placed into the gray zone to stop the slip-

pery slope from moving forward. This form of attack was in fact

the move made in the designer babies example.

What makes a slippery slope slippery is this gray zone, and

what makes the gray zone possible is indeterminacy of a kind

that offers no clear and precise point demarcating the action at

which the agent will lose control, and afterwards descend inevi-

tably to the catastrophic outcome. However, legal argumentation

is full of cases where laws are enacted by legislatures and then

interpreted by court rulings that tighten up the open texture of

terms that are difficult to precisely define. In some cases these

proposed criteria do not work very well, for example because

they lead to a law that is unenforceable. But in other cases the

proposed criteria work very well, especially when they are test-

ed and refined by new cases that challenge them. The procedure

is one of case-based reasoning, where laws are applied to cases

using precedents from previous cases. In other words, law al-

ready has a working system in place for dealing with slippery

slope arguments, or even preventing them from arising. Law al-

so illustrates the possibility of finding a bright line by devising a

legal rule that can be used to cut through the gray zone prevent-

ing the slippery slope from descending to the catastrophic out-

come.

The following objection seems to pose a problem. A slippery

slope critique seems to express the message that the critic is ad-

vising the proponent not to take the initial step, for even by not

taking the initial step she might already lose control. It would

seem that if not, the proponent could easily answer: “Thanks for

the warning, but I will stop before I enter the gray area.” This

possibility seems to pose in connection to the basic argumenta-

tion scheme as a model of the logical form of slippery slope ar-

guments, because it seems that the initial action must already

The Basic Slippery Slope Argument

303

reside within the gray zone, contravening the requirements of

the basic scheme.

The reply to the objection is that as the slippery slope argu-

ment is stereotypically used, it is not meant to advise the propo-

nent not to take the initial step for the reason that even at this

initial step she might already lose control. That is an additional

argument that might optionally be added on in some cases. The

critic might add, in a case about considering trying heroin for

example: “Some people can resist taking heroin even after trying

it several times, so it is possible that you could stop before en-

tering the gray area, but there are also some rare instances where

once a person has taking this drug even once, the impact is so

pleasurable that she cannot resist trying it again.” However, this

additional argument should not be seen as part of the slippery

slope argument. It is an add-on that might make the argument

even powerfully persuasive to some respondents. But also runs

the risk of seeming unpersuasive to others. For example adoles-

cents can be very suspicious that warnings about taking drugs

are exaggerated and used as scare tactics.

There is also another objection to be considered. The nature

of slippery slope arguments being what they are, they are argu-

ments about what might or will happen in the distant future. A

critic might say therefore, that it is impossible to prove or dis-

prove them. But this is too harsh a stance. We use arguments

that depend on predictions about the future all the time. Argu-

mentation from negative consequences is one of the most com-

mon forms of argument in human deliberations, and it is an ar-

gument about what can or will happen in future. The problem

with slippery slope arguments is that they generally are about

what will happen in the distant future if you carry out a particu-

lar action now that might lead to a lengthy sequence of actions

resulting in some highly unpleasant outcome over the long term

at some endpoint. Of course a critic can try to respond to such

an argument by saying that it’s all speculation. But if the audi-

ence is worried enough about the catastrophic outcome, and if

the audience is inclined to accept the premises of the slippery

slope argument, even if they have not been explicitly stated or

supported by the proponent, this type of argument can be power-

fully persuasive. Indeed, we have argued here that it can be in

principle a reasonable argument in some instances, if supported

well enough by the evidence that is available, even though it re-

quires extrapolating the argument quite a distance into the fu-

ture.

Douglas Walton

304

For these reasons, a line of counterattack that is very im-

portant for a critic to work on is to argue that a bright line crite-

rion can be furnished that will stop the slippery slope by dissi-

pating the gray zone. This line of attack can be put forward even

if the critic does not know at the present time how that bright

line will be defined precisely, or even what it is. For as argued

above, it could be quite possible that the legal system can do

away with the slippery slope by means of its usual methods of

case-based reasoning, and testing criteria in trials.

10. Conclusions and further research tasks

In this paper, it has been shown that slippery slope arguments

are in principle reasonable arguments, or can be, because they

are a species of arguments from negative consequences. These

findings support the conclusion drawn by Govier (1982, 316)

that a slippery slope argument may make many mistakes, but

need not make any. Slippery slope arguments can be reasonable

in some cases of intelligent deliberation, as shown by the exam-

ple of advice-giving deliberation in which the father advises his

son that taking drugs would not be a good idea because it can

lead to loss of control resulting in a catastrophic outcome. A

reasonable slippery slope argument of this kind has four basic

characteristics that can be summed up as follows. First, there

must be a framework of deliberation in which one agent is ad-

vising another on a choice of action. Second, there must be a

sequence of actions leading from the action to be chosen to an

ultimate outcome. Third, there must be a gray area in the middle

region of the sequence in which the agent will lose control.

Fourth, once the agent has lost control, he or she will be im-

pelled along the sequence leading to an ultimate catastrophic

outcome.

It has also been easy to assume that the slippery slope argu-

ment is fallacious for three reasons: (1) because it is a long-term

argument that goes far into the future and necessitates long-term

planning, (2) because it is such a complex form of argument that

it is hard to grasp its structure, and (3) because it is often associ-

ated with arguments on euthanasia and eugenics and the like,

arguments that seem exaggerated because they make emotional

appeals and use emotional terms such as “euthanasia” and “eu-

genics” associated with mass murder programs of the Nazi peri-

od in Germany (Bashford and Levine, 2010).

The Basic Slippery Slope Argument

305

Because slippery slope arguments typically go so far into the

future, and have so many additional components than the more

common kinds of arguments from negative consequences, they

are hard to support, but they need much support, often empirical

support deriving from the circumstances of each individual case.

To be a slippery slope argument, an argument has to fit the re-

quirements of having the right premises and conclusion to fit the

argumentation scheme for that type of argument. The argumen-

tation scheme proposed in this paper helps with this job by car-

rying through a series of steps in the procedure for the identifi-

cation method. Allied with better knowledge of how the basic

slope argument is related to its subtypes, such as the linguistic,

causal and precedent types, the basic scheme is a tool useful for

analyzing and evaluating slippery slope arguments.

This paper goes some way toward casting doubt on the thesis

of Lode (1999, 1492) that there is no single distinctive form of

the slippery slope argument. His argument is based on the prem-

ise that different slippery slope arguments hold that stepping on

the slope is objectionable for different reasons. The conclusion

he has drawn is that slippery slope arguments are a family of

related arguments rather than a class of arguments whose mem-

bers all share the same form. To conclusively refute this thesis

we would need to analyze a large and representative number of

examples of slippery slopes, including many from law, and

show that all of them can be shown to be instances of the basic

slippery slope argumentation scheme. This task can be proposed

as a topic for further research in which the hypothesis to be test-

ed is the scheme for the basic slippery slope proposed in this

paper. The procedure required to apply this scheme to examples

that purport to be genuine instances of slippery slope arguments

has been built in this paper.

As applied to instances of the slippery slope argument, the

procedure has the following steps. First of all, frame the argu-

ment in a context of deliberation in which one agent is giving

advice to another. One of the agents is contemplating taking

some particular step, and the other is advising the first agent not

to take that step because it will lead forward by a sequence of

actions that will, during a gray zone, run out of control leading

to an outcome that the second agent evaluates as highly nega-

tive, catastrophic or intolerable. Once the argument has been

situated in this context of a deliberation, the next step is to see if

it has all of the characteristics of the slippery slope argument.

For these purpose the application of the basic argumentation

scheme for the slippery slope type of argument to the textual

Douglas Walton

306

data of the given argument is required. Some arguments that are

said to be slippery slopes and that look like a slippery slope may

not fit all of the requirements. In particular, it is necessary to

analyze the given argument to find the three key components of

it, the gray zone, the sequence and the drivers.

For length reasons, naming and classification issues were not

extensively treated in this paper. Various other names for the

slippery slope argument, such as the thin edge of the wedge ar-

gument, the dam bust argument, the camel’s nose in the tent ar-

gument, and so forth, are present in the literature. No serious

attempt has been made to confront the issue of whether these

terms are equivalent to the slippery slope name, or whether they

represent different types of arguments related to the slippery

slope argument, such as species of slippery slope argument. This

subject can also be further investigated using the basic scheme.

The contextual variability of use of the slippery slope argu-

ment, and related types of arguments it is built on, such as ar-

guments from goal-directed practical reasoning and arguments

from negative consequences is a high level problem that cannot

be solved in this paper. But it is an important problem, and some

analysis of how it impacts on the analysis of the slippery slope

argument put forward in this paper are useful. Those writing on

biomedical issues concerning the slippery slope argument tend

to see the framework of its use as a deliberation dialogue in

which one party is considering carrying out a particular action,

such as a genetic intervention, and the other party in the dia-

logue is using a slippery slope argument to suggest that carrying

out this section would be the first step in the sequence of follow-

ing events that might lead to a disastrous outcome. Commenta-

tors treated above such as Corner et al., Saliger, and Holtug, fall

into this category. However, as the six basic characteristics of

the slippery slope argument proposed in (Walton, 1992, 208)

make clear, this analysis is much broader, because it includes

cases of slippery slope arguments used in other types of dia-

logue, such as persuasion dialogue and negotiation dialogue.

This analysis is based on a dialectical framework where the

steps in the slippery slope argument are modeled through the

device of a commitment store in a dialogue. The commitment

store is a database of propositions such that at each step of the

slippery slope argument, as it unfolds in the dialogue between

the two sides, propositions can be inserted into the database or

deleted from it, depending on the dialogue protocol and the

kinds of speech acts put forward by each party unity to move.

The Basic Slippery Slope Argument

307

Each instance of an argument in a natural language text is

different and needs to be treated as an individual case, but for-

mal models are sometimes very useful tools to set out normative

requirements for what should count as a correct argument of a

particular type. Argumentation schemes need to be part of such

more formal models, and many tools commonly used in argu-

mentation and informal logic such as argument diagrams have a

formal structure. Informal logic is a field of study that grew

from the perception that the formal methods used during the

20th century, especially classical deductive logic, were not as

useful as one might like to study real examples of argumentation

in natural language. Formal argumentation methods developed

in computer science took this challenge seriously, and responded

by offering more flexible formal systems and tools designed to

be helpful for the tasks of informal logic. These tasks were taken

to include the identification, analysis and evaluation of argu-

ments, and even the task of argument invention. The outcome of

these developments is that argumentation theory has grown into

an interdisciplinary area that integrates and applies tools and

methods from different fields. This interdisciplinary aspect of

argumentation was made clearly apparent in a recent invitation

from the director of the Leibniz Center for Informatics to the

author to participate in a one-week Schloss Dagstuhl3 seminar in

Germany entitled Natural Language Argumentation: Mining,

Processing, and Reasoning over Textual Arguments. The state-

ment was made in the invitation that because argumentation is

an inherently cross-disciplinary topic involving philosophy,

communication studies linguistics, and computer science, where

different interpretations, analyses, and uses of arguments are

proposed and applied, there needs to be progress not only within

each domain, but also in bridging these various disciplines.

The literature on formal argumentation systems has now been

expanded to include formal multiagent deliberation dialogue

systems based on practical reasoning (McBurney, Hitchcock and

Parsons, 2007; Kok et al., 2011; Medellin-Gasque, et al., 2011),

a form of argument closely related to slippery slope arguments.

It is important for new research on such arguments to take such

formal argumentation systems currently being developed in mul-

tiagent systems research and artificial intelligence into account.

Now that formal argumentation models of dialogue are available

in which slippery slope arguments and related arguments such as

3 Dagstuhl supports computer science by organizing advanced seminars on

current topics and problems in informatics that bring together personally

invited scientists from academia and industry from all over the world.

Douglas Walton

308

argument from negative consequences can be modeled, re-

searchers studying informal logic should take advantage of the

tools they provide.

The primary type of dialogue in which slippery slope argu-

ments are used, for example in biomedical issues about genetic

therapy, is deliberation dialogue. In this type of dialogue one

agent, the proponent, is faced with a decision about what to do

in a particular set of circumstances, and the other agent, the re-

spondent, is playing the role of critic by asking critical questions

and putting forward counterarguments directed to the action the

proponent has tentatively chosen to go forward with (McBurney,

Hitchcock and Parsons, 2007; Kok et al., 2011; Medellin-

Gasque, et al., 2011).). This type of dialectical situation is the

prototypical case in which forms of argument such as argument

from negative consequences and the slippery slope argument are

primarily used. The contribution of this paper is to provide a

basic argumentation scheme for the slippery slope argument that

can be fitted into the broader framework of the analysis of slip-

pery slope arguments given in (Walton, 1992) that is commit-

ment-based, and that covers uses of slippery slope arguments in

other types of dialogue as well as that of deliberation.

Further research is also needed to show more precisely how

the slippery slope scheme is related to the scheme for practical

reasoning, a scheme that is very closely related to the scheme

for argument from negative consequences. Especially important

in this regard is the scheme for value-based practical reasoning.

In an argument from negative consequences, the consequences

are described as “bad” or “negative,” meaning that they are low

in a preference ordering exhibiting a scale of values representing

the values applicable in a particular case. Similarly, in a slippery

slope argument, the ultimate outcome is described as a catastro-

phe, implying that it has to be very low on the preference order-

ing, so low that it is imperative to take steps to avoid it.

How these factors work in to the analysis of the slippery slope

argument is a subject of argumentation research that needs to be

investigated in more detail. Although slippery slope arguments

are complex, because they are made up of a network of simpler

arguments nested together into the one large argument, the best

way to grasp their complexity and help us to understand them is

to classify this cluster of arguments so that it can be shown how

the slippery slope scheme is built up from other schemes, such

as argument from negative consequences. Although the basis for

this work is built in the present paper, continuing it requires a

The Basic Slippery Slope Argument

309

research on classification of argumentation schemes covering all

the known schemes.

Another main problem arising from the paper was that of

dealing with compressed slippery slope arguments, arguments

that are claimed to be slippery slope arguments that are ex-

pressed in such a compressed form that many of the necessary

ingredients for this type of argument are not explicitly stated.

What needs to be done in such cases is to use the basic argumen-

tation schemes to search the text of discourse in a given case for

the missing elements by using the basic argumentation scheme.

This procedure is a typical argumentation task associated with

enthymemes, arguments with missing premises or a missing

conclusion. It can be used to help evaluate arguments, such as

the slippery slope argument, using formal argumentation sys-

tems currently being developed in AI, such as ASPIC+ and

CAS. Dealing with these problems is beyond the scope of this

paper, but enough of the structure of the slippery slope argument

has now been identified to provide a basis to help this research

work move forward.

Acknowledgements

The research for this paper was funded by Insight Grant 435-

2012-0104 from the Social Science and Humanities Research

Council of Canada.

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Oct 2022

Sergei L. Mosyakin

Smith & al. (2022), Hammer & Thiele (2021), and some other authors recently discussed and proposed dramatic changes to the International Code of Nomenclature of algae, fungi, and plants (ICN) aimed at the provisions allowing rejection and replacement of valid and legitimate names that reflect the “colonial and imperialist power” or may be considered, at least by some experts and users, as “culturally offensive or inappropriate” because of several broadly and vaguely formulated reasons, such as names considered to be “derogatory or insulting to a person or group of people”, those honoring “a person that the taxonomic community agrees should not be honoured”, and even any name that “otherwise causes deep offense”. These proposals and their possible outcomes were analyzed and criticized in my article (Mosyakin, 2022), which was, in turn, criticized in a recent article by Smith & al. (2022). In the present note I respond to that criticism, discuss additional cases of possible “culturally offensive or inappropriate” names, and provide additional evidence of possible (and, in my opinion, highly probable) confrontational and disruptive outcomes in case if the proposals to reject “culturally offensive or inappropriate” names are accepted and incorporated into the ICN. I appeal to the international community of taxonomists to reject such proposals, to protect the fundamental Preamble 1 and Art. 51 of the ICN, to protect the scientific freedom and principles of nomenclatural stability and political neutrality, and to protect our science from politically motivated decisions. The Pandora's Box of anticipated fights for or against “culturally offensive and inappropriate names” should remain firmly closed. Scientists in general and plant taxonomists in our case should firmly stand for the common values of scientific freedom, mutual understanding and respect, tolerance, reconciliation, a bold, open-minded and honest view of history (including history of taxonomy), and, specifically, the principle of neutrality of biological nomenclature well expressed in Art. 51 of the ICN. Essentially the same provisions in earlier versions of the Code or other earlier rules of botanical nomenclature served well the generations of taxonomists and users of taxonomic information, preventing unnecessary conflicts between people and peoples over names of organisms, which someone sometime somehow may or may not consider “culturally offensive or inappropriate”. Preamble 1 and Art. 51 of the ICN are crucial tools for maintaining nomenclatural stability, civility, and tolerance in our diverse, complicated and, unfortunately, not so peaceful present-day world, and especially in our science of biological taxonomy reflecting the amazing diversity of the living world of our planet. FREE ACCESS.

Opinion of Medicine Faculty Students about Abortion (Gazi University Case)

Article

Sep 2022

öğrencilerinin kürtaj ile ilgili görüşlerinin saptanması amacıyla yapılmıştır. Araştırmaya ilişkin veriler Gazi Üniversitesi Tıp Fakültesi’nde öğrenim gören 1., 4. ve 6. sınıf öğrencilerine uygulanan soru kâğıdı ile toplanmıştır. Örneklem, basit rastgele örnekleme yöntemi ile belirlenmiştir. 1358 öğrenciden 698’ü soru kâğıdını doldurmuştur. Döllenmeden itibaren, “Sizce fetüsün birey sayılması için, sınır kaçıncı hafta olmalıdır?” şeklindeki soruya tıp fakültesi öğrencilerinin %32,0’ı kalp atımının başladığı zaman olan 6. haftayı belirtmiştir. Öğrencilerin %26,0’ü ise bu sınırı döllenmeden itibaren çizmiştir. Çalışmada görüldü ki öğrencilerin çoğu (%81,2) kürtajı bir doğum kontrol yöntemi olarak görmemektedir. Kürtajın bir gerekçesi olarak annenin ileri derece mental retarde olması ya da annede ölümcül bir hastalığının olmasının gösterilmesine çoğu öğrenci kararsız kalmıştır. Öğrencilere kürtaj hakkında babadan izin alınması ile ilgili görüşleri de sorulmuştur. Buna göre öğrencilerin çoğu (%81,0) anne ve babanın evli olması durumunda babadan izin alınması gerektiğini düşünürken, evliliğin olmaması durumunda ise görüşlerinin değiştiği, yüzdelerin babadan izin alınmasının gerekli olmadığı yönüne doğru kaydığı görülmüştür. Araştırmada ayrıca öğrencilerin %57,0’ı kürtajın yasal sınırı olarak gebeliğin 10. haftasını uygun bulmuş ve çoğu öğrenci (%67,9) kürtajın tamamen yasaklanmasına karşı olduklarını belirtmiştir. Araştırmada tıp fakültesi öğrencilerine örnek verilen kürtaj olgusu ne kadar karmaşıksa yani ele alınması gereken etik ilke ne kadar çoksa, yaşadıkları etik ikilemin o derecede fazla olduğu görülmüştür. Ayrıca öğrencilerin kararlarını etkileyen önemli faktörlerden birinin Türkiye’nin kürtaj ile ilgili mevcut yasal düzenlemeleri olduğu görülmüştür.

Critical Thinking: The Basics

Book

May 2023

Stuart Hanscomb

Justifying Violent Protest: Law and Morality in Democratic States

Book

Dec 2022

James Richard Hugh Greenwood-Reeves

The Social Psychology of Tolerance

Book

Oct 2022

Maykel Verkuyten

Thirty years of Artificial Intelligence and Law: the first decade

Article

Full-text available

Sep 2022
Artif Intell Law

The first issue of Artificial Intelligence and Law journal was published in 1992. This paper provides commentaries on landmark papers from the first decade of that journal. The topics discussed include reasoning with cases, argumentation, normative reasoning, dialogue, representing legal knowledge and neural networks.

Argumentation Skills for the Design of Formative Assessment Queries

Chapter

Apr 2022

This chapter surveys the benefits of critical and argument skills in bilingual pre-service teachers' future careers for assessment pursuits. It also examines how informal logic for pedagogical purposes is scarcely considered in education settings – both primary and university levels. Yet, such a lack of teacher training will negatively influence subsequent feedback and ad hoc formative assessments to measure bilingual pupils' knowledge accurately. Hence, taking as referents argumentation and critical thinking and enquiring, the chapter aims to establish the fundamental theoretical foundations for understanding and designing formative queries.

Implicatures as Forms of Argument

Chapter

Full-text available

Nov 2013

In this paper, we use concepts, structure and tools from argumentation theory to show how conversational implicatures are triggered by conflicts of presumptions. Presumptive implicature are shown to be based on defeasible forms of inference used in conditions of lack of knowledge, including analogical rea-soning, inference to the best explanation, practical reasoning, appeal to pity, and argument from cause. Such inferences are modelled as communicative strategies used to fill knowledge gaps by shifting the burden of proof to provide the missing contrary evidence to the other party in a dialogue.c Through a series of illustrative examples, we show how such principles of inference are based on common knowledge about the ordinary course of events shared by participants in a struc-tured dialogue setting in which they take turns putting forward and responding to speech acts. Keywords Argumentation Á Implicatures Á Argumentation schemes Á Analogy Á Speech acts Á Pragmatics Á Implicit speech acts Á Indirect speech acts The notion of implicature was introduced by Grice in 'The Causal Theory of Perception' (Grice 1961) and developed in his further essays (Grice 1975) 1 . The theory is meant to describe the relationship between what is said and what is meant in cases in which the conventional meaning commonly associated with the sen-tence (''what is said'') does not correspond with the speaker's communicative intention, or his/her intended effect on the audience (''what is meant'') (Grice

Arguments over Co-operative Plans

Conference Paper

Full-text available

Jul 2011

Autonomous planning agents that share a common goal should be able to propose, justify and share information about plans. To reach an agreement on the best plan, strategies for persuasion and negotiation could be used by agents in order to share their beliefs about the world and resolve conflicts between the agents. We present an argumentation scheme and associated critical questions to create and justify plan proposals where plans are combinations of actions requiring several agents for their execution. An analysis of different ways in which actions can combine is presented and then associated with the argumentation scheme and the critical questions. We believe these elements are necessary to enable agents to engage in rational debate over co-operative plan proposals.

Logic and conversation

Article

Jan 1991

H.P. Grice

The camel's nose is in the tent: Rules, theories, and slippery slopes

Article

Dec 2003
UCLA LAW REV

Slippery slopes have been the topic of a spate of recent literature. In this Article, the authors provide a general theory for understanding and evaluating slippery slope arguments and their associated slippery slope events. The central feature of the theory is a structure of discussion within which all arguments take place. The structure is multilayered, consisting of decisions, rules, theories, and research programs. Each layer influences and shapes the layer beneath: Rules influence decisions, theories influence the choice of rules, and research programs influence the choice of theories. In this structure, slippery slope arguments take the form of meta-arguments, as they purport to predict the future development of arguments in the structure of discussion. Evaluating such arguments requires knowledge of the specific content of the structure of discussion itself. This Article then Presents four viable types of slippery slope arguments; draws attention to four different factors that, other things equal, tend to increase the likelihood of slippery slopes; and explores a variety of strategies for coping with slippery slopes.

Introduction: Eugenics and the Modern World

Article

Jan 2010

This article summarizes both the history and the historiography of eugenics across the world and that indicates new lines of inquiry that have evolved in recent years. It demonstrates that eugenics rapidly has become a shared language and ambition in cultures and locations that were otherwise radically different. It discusses the complicated relationship between the unconditional advocacy of contraception by neo-Malthusians and the cautious ambivalence typical of eugenicists. This article extends the analysis of eugenics through gender by addressing the question of masculinity and the subjectivity of eugenic advocates. This article analyzes the transnational themes in eugenics and surveys the important question of place-based differences in eugenic aims, methods, policies, and outcome. Eugenics invokes a modern political history in which individuals have been subsumed within collectives and their perceived interests and soon became a signal for, and almost a symbol of, modernization.

Straight and crooked thinking

Article

Jan 1953

Logic and conversation, in P

Article

Jan 1967
SYNTAX SEMANTICS

H. Paul Grice

Slippery Slopes

Article

Dec 1985
HARVARD LAW REV

Frederick Schauer

Arguments of the "if this, then that, and finally that" variety have a long heritage in legal and popular discourse. They appear in all fields of law and seem especially common in Professor Schauer's own area of expertise: free speech law. In this Article, Professor Schauer examines the presuppositions and defining characteristics of slippery slope arguments. His aim is not to defend or debunk such arguments, but to distinguish them from other arguments often couched in slippery slope form, and through this process of analytic isolation to expose the foundations on which slippery slope claims must stand or fall. He argues that slippery slope arguments depend for their persuasive power on the currently perceived inability of future decisionmakers to recognize, comprehend, or defend doctrinal lines drawn by their predecessors. Hence, Professor Schauer concludes, slippery slope arguments may flourish in law because of the unique way in which law, set apart from other disciplines, pays allegiance to the past while guarding the future.

The application of logic

Article