Laws, Contingencies, Irreversible Divergence, and Physical Geography*

Abstract

Four critical challenges for physical geography are examined here: deterioration of common cores of knowledge associated with increasing intellectual niche specialization; the need for conceptual thinking and problem-framing to catch up with measurement and analysis technology; and the need to explicitly incorporate human decision making in analysis of earth surface systems. The future calls for physical geography to embrace and confront the creative tension between nomothetic and interpretive science, and to fruitfully and explicitly integrate these approaches.

Full text

Laws, Contingencies, Irreversible Divergence,
and Physical Geography
*
Jonathan D. Phillips
University of Kentucky
Four critical challenges for physical geography are examined here: deterioration of common cores of knowledge
associated with increasing intellectual niche specialization; the need for conceptual thinking and problem-
framing to catch up with measurement and analysis technology; and the need to explicitly incorporate human
decision making in analysis of earth surface systems. The future calls for physical geography to embrace and
confront the creative tension between nomothetic and interpretive science, and to fruitfully and explicitly
integrate these approaches. Key Words: contingency, irreversible divergence, laws, physical geography.
Physical geographywill continue to grow and
thrive in the next century, but in the next
decade or so we face some critical challenges.
Notwithstanding comments on divergence and
fragmentation—a factor in the evolution of phy-
sical geography that can hardly be ignored—
the focus will be on the future of physical geog-
raphy as science and scholarship, rather than
on physical geography as a discipline or sub-
discipline. The extent to which the execution of
physical geography will be called geography,
or associated with the institutions of geog-
raphy, is not my concern here. This is not to say
that such questions are not important; it is
an acknowledgement that your guess is as good
as mine.
1
Irreversible Divergence
The increasing fragmentation and specializa-
tion in geography—and every other field—is
sometimes attributed to the poor fit between the
historically contingent, artifactual definitions
of the traditional academic disciplines and the
world we perceive and study. This is not
the primary driver of fragmentation, however.
We are becoming ever more specialized because
we have no choice.
As knowledge expands, the ability of any
individual to cope with it stays constant, oblig-
ing (succeeding generations of ) individuals to
specify increasingly narrow intellectual niches.
Specialization and fragmentation is inevitable
and unavoidable. As intellectual niche speciali-
zation occurs, specialists become increasing-
ly removed from traditional disciplinary cores.
This is not entirely—and not necessarily—a bad
thing. New, specialist groups may be indepen-
dent of unhealthy or stifling cultures, politics,
authorities, and orthodoxies of the traditional
disciplines. There is also the potential for fruit-
ful interchanges and synergies, drawing from
different scientific cultures as well as different
knowledge bases, skills, and abilities.
On the negative side, fragmentation may lead
to scattered individuals and groups of specialists
who operate with no central frame of reference
or core base of knowledge or epistemology.
This lack of a common core may inhibit com-
munication within and between the specialist
groups, and may also be inefficient as wheels are
reinvented. The emergence of new cores inde-
pendent of the traditional disciplines is possible,
but is inhibited by the absence of central insti-
tutions and authorities to define, negotiate, or
enforce a common body of knowledge. There-
fore, as these cores emerge, the common body
of knowledge is likely to be ad hoc and main-
tained by informal networks.
The primary implication of divergence for
the science of physical geography, given the in-
evitability of increasing specialization, is the
likelihood that earth and environmental scien-
tists will increasingly operate without a central
body of knowledge or core epistemology. This
will serve as a negative feedback or brake on the
* Three anonymous reviewers and both guest editors provided detailed, thoughtful, and stimulating commentary and critique. I regret that limitations
of time, allotted space, and my abilities kept me from responding effectively (or at all) to many of their excellent suggestions and comments.
The Professional Geographer, 56(1) 2004, pages 37–43 rCopyright 2004 by Association of American Geographers.
Published by Blackwell Publishing, 350 Main Street, Malden, MA 02148, and 9600 Garsington Road, Oxford OX4 2DQ, U.K.

progress that specialization, coupled with steadi-
ly improvingcommunicationstechnology, might
otherwise facilitate. Alas, I have no recommen-
dations, other than that issues of a shared core
of knowledge should be considered as both
traditional disciplines and specialist groups plan
their futures. Human geography, communica-
tion studies, and the history of science may
provide useful insight or models in this regard.
Theory, Technology, and
the New Classics
Remarkable technical advances are underway,
revolutionizing many threads of inquiry, reinvi-
gorating moribund areas of study, and opening
up lines of investigation the previous generation
could scarcely have imagined. A review would
require a lengthy book, but these advances in-
clude new measurement methods and tech-
niques ( for example, in remote sensing, dating,
and mass flux tracing), new analytical tech-
niques ( for instance, local forms of spatial analy-
sis and object-oriented GIS), and new ways to
dramatically increase the amount and availabil-
ity of traditional types of data (such as digital
elevation models and paleoecological data). The
new techniques and technologies both allow
us to do things we could never do before, such as
date previously undatable materials and sur-
faces, and enable us to perform traditional tasks
with previously unheard-of scope and speed,
such as LIDAR-based topographic mapping.
These advances come from withinphysical geog-
raphy and its subdisciplines, from evolving inter-
faces (genetics/biogeography or geochemistry/
geomorphology, for instance), or from simply
making use of general technological improve-
ments in fields such as computation and micro-
scopy. It may now be the case that our ability
to measure is no longer the major factor limit-
ing the advancement of physical geography.
This is not to say that there is not plenty of
room left for technology-based advancement.
For physical geography in the aggregate, how-
ever, our ability to measure and model has
temporarily outstripped our knowledge of exact-
ly what we should be measuring or modeling
and our supply of good ideas and important
problems. With new dating techniques, for
instance,we are now able to test somehypotheses
regarding long-term landscape evolution, such
as whether landforms are (or can be) in steady-
state equilibrium, and mitochondrial DNA
analysis allows biogeographers to examine evo-
lutionary biogeography in new ways. In another
example, new ice-core data, enabled by im-
proved ice-drilling technologies, allows the eva-
luation of hypotheses regardingclimate changes.
We are well along in the application of new
methods and data to classic problems. As pre-
viously unanswerable questions gradually get
answered, the future growth of the field will
depend largely on our ability to define interest-
ing and important new problems. As we address
the vintage problems of the nineteenth and
twentieth centuries, our challenge is to frame
a set of new or future ‘‘classic’’ problems. The
situation may be analogous to that of hydrology
twenty years ago, when David Pilgrim (1983,
71) claimed that ‘‘[O]ur analytical ability has
far outstripped our knowledge of hydrological
processes.’’ Since then, hydrological knowledge
has been greatly increased, at least partly due
to technological advances such as isotope tra-
cers, but Jeffrey McDonnell (2003) reports that
these techniques are being applied to decades-
old conceptual models that need updating or
replacement. Perhaps the development of phys-
ical geography and its subdisciplines is des-
tined to be staggered, as theory or technology
moves ahead and then waits for the other to
catch up.
At the risk of caricature, confronting this
challenge implies a revitalization of curiosity-
driven, individual-oriented ‘‘small science,’’ as
opposed to funding- and technology-driven,
research-group-oriented ‘‘big science.’’ The
most important and fundamental ideas, theo-
ries, and hypotheses in physical geography
arise from real-world observations, be they the
classic constructions of Cowles, Gilbert, Davis,
or Dokuchaev or more recent insights such
as evidence of abrupt climate or vegetation
changes in paleoenvironmental data. The effort
to advance theoretical physical geography in
the near future will be less about algorithmic or
laboratory skill and more about generating
ideas about soils, ecosystems, climates, and
so on. For most physical geographers, these
ideas come from the field—whether via formal
fieldwork, rambling around the countryside or
streetscape, or observations through an air-
plane window. Thus, a key limitation on our
near-future development may be the extent to
38 Volume 56, Number 1, February 2004

which we engage the Earth on its own terms,
as opposed to via stripped-down representa-
tions of the Earth in simulation models or
laboratories.
Human Impacts
No geographer needs to be convinced about
the overwhelming impact of homo sapiens on the
global environment, and most still buy into,
at some level, the value of synthesizing human
and ‘‘natural’’ science and scholarship. Physi-
cal geography will continue to make important
contributions to understanding human impacts
on the environment. The combination of natur-
al science and social science is relatively com-
mon when one or the other is treated at the
vernacular level. Integration, where both phys-
ical and human geography are dealt with at a
high level of sophistication, is rare ( Johnston
1986); generally, either human agency or bio-
physical processes are treated as inputs or
boundary conditions to the other, which is the
focus of theorizing, analysis, and prediction.
Increasingly, that will not be good enough.
That is, human impacts in some systems are
so pervasive that we cannot understand and pre-
dict these biophysical systems without account-
ing for economic, social, and cultural boundary
conditions and forcings just as we dutifully
account for climate, tectonics, and sea level.
Much has been accomplished with more tra-
ditional approaches based mainly on compar-
ing and contrasting more-or-less-unaltered with
human-altered systems, but we are approach-
ing the limits of what we can do. In many
situations, explanation requires incorporating
human decision making and actions into con-
ceptual frameworks and predictive models. For
instance, Karl Nordstrom (1987) showed that
the response of New Jersey tidal inlets to sea-
level rise or coastal storms cannot be predict-
ed based strictly on coastal geomorphology.
Rather, human responses such as dredging,
beach nourishment, shoreline ‘‘hardening,’’
and other actions must be considered along
with geomorphic processes (Nordstrom 1987).
I stress that my arguments here are indepen-
dent of any notions of the unity of physical and
human geography and of explicit concerns
with human environments or natural/social-
science integration. My claim is that even if one
is only interested in hillslopes, ecosystems, or
evapotranspiration,with no professionalconcern
with human activities or behavior, human agency
must still be engaged, because there is often
no way to understand hillslopes, ecosystems, or
evapotranspiration—for example—without it.
Cultural ecology and geoarchaeology pro-
vide a number of examples of studies in which
both physical and human geography data and
principles are brought to bear, with comparable
levels of attention and sophistication. There
are not many exemplars in studies of modern
technological societies or landscapes, or where
environmental and resource effects on humans
are less central than in cultural ecology. One
exception is Martin Roberge’s (2002) study of
channel changes in the Salt River, which puts
the actions of planners and engineers on an
equal analytical footing with the dynamics of
flow and sediment flux. Others include the work
of R. P. Guyette, R. M. Muzika, and D. C. Dey
(2002) on anthropogenic fire regimes and forest
ecology in the Missouri Ozarks, and S. Sullivan
and R. Rohde’s (2002) integration of biogeog-
raphic, ecological, land-use, and political-
economy theoryin problems of land degradation
in semiarid Africa. These examples notwith-
standing, we are a long way from—for example
—a fluvial project in which stream power and
political power are both brought to bear on
studies of channel change.
Laws and Contingencies
Science is characterized by creative tension
between a search for fundamental laws and
generalities that are independent of place
and time and the recognition—particularly in
the earth and environmental sciences—that
geography and history matter. The law-based,
nomothetic approach (often, but not necessa-
rily, reductionist) seeks explanation based on
the application of laws and relationships that
are valid everywhere and always. Particularities
of place and time are not ignored, but they
are treated as boundary conditions and are
not a causal or necessary part of explanation.
Alternative approaches, which may be termed
idiographic, historical, or interpretive, seek
explanation based on the particular details of
site, situation, and history. General laws are
acknowledged and utilized, but as constraints
and context to the specific events, objects, or
situations that are the basis of explanation.
Laws, Contingencies, Irreversible Divergence, and Physical Geography 39

The nomothetic approach has generally been
dominant, and arguably so in the earth and envi-
ronmental sciences, even as numerous geog-
raphers, geologists, ecologists, archaeologists,
soil scientists, and others have quietly and effect-
ively practiced historical, interpretive science.
The idiographic approach has often been viewed
as a necessary precursor to more advanced
nomothetic schemes, as a temporary fallback
option when we are not yet up to recognizing
or applying general laws, or as being carried
out in the service of law-based science to pro-
vide necessary inputs and boundary conditions
to the latter.
Recently, however, approaches to science
based on or recognizing historical and spatial
contingencies and path dependence have been
reconceptualized as legitimate and necessary
methodologies on an equal footing with nomo-
thetic methods. In general terms, this new view
holds that:
Some scientific fields—particularly those
with important historic components and
those which deal with nature on its own
terms, rather than a laboratory or model
setting—have innate, irreducible levels of
contingency that cannot be reduced or
eliminated by simply collecting more data
or by refining law-based models.
Historical and interpretive approaches,
while different from the laboratory-
experimental ideal of nomothetic science,
may be equally sophisticated and valid
ways of gaining knowledge, independent-
ly of any relationships with nomothetic
science.
The operations and manifestations of
earth systems are often characterized by
contingent factors that may have sig-
nificant—even predominant—influences
on system states and outcomes. That is,
contingencies are not necessarily noise
superimposed on patterns determined by
general laws, or complications that can
eventually be described by general laws.
They may be factors which are irredu-
cibly place- and/or time-dependent, and
which may be as important as or even
more important than general laws in de-
termining how the world works.
Geography and earth science often deal
with singular, nonrepeatable outcomes
(the state of a landscape or system at a
given time and place). Thus, the ideals
of repeatability and experimentation of
the laboratory sciences are often not
applicable.
These arguments have been particularly com-
mon and forceful in geomorphology and geol-
ogy (e.g. Frodeman 1995; Baker 1996; Lane and
Richards 1997; Spedding 1997; Bishop 1998;
Harrison 1999), in ecology and biogeography
(Foster 2000; Peterson 2002; Phillips 2002),
and in paleontology and evolutionary biology
(Gould 2002), but have also been voiced in
pedology (Kristiansen 2001; Phillips 2001a),
and in physical geography ( Phillips 2001b;
Sauchyn 2001).
The search for underlying laws and general-
ities will continue to be a fundamental goal.
However, it has become clear that in many cases,
full explanation and understanding based on
general laws alone is impossible or unfeasi-
ble. Thus, the challenge is to fully integrate
nomothetic and idiographic approaches—to
move from methods that place either historical
and geographical particulars or general laws
in a clearly secondary position to those that
give equal or comparable weight to laws and
contingencies.
In no science is this more important than in
physical geography. As in geology, archaeology,
and evolutionary biology, history is critical in
physical geography. And as in other aspects of
geography, place is critical as well. While there
are certainly problems that can be solved based
on a strictly nomothetic approach, in physical
geography contingencies are always present and
often relevant.
While the challenge of integrating laws and
particularities is more acute for physical geog-
raphy than perhaps any other discipline, there
are several reasons that physical geography is
in a good position to take a leadership or exem-
plary role in this synthesis. Physical geography
has been here before, largely via its associa-
tion with regional and human geography. The
debates over idiographic/regional/interpretative
geography versus nomothetic /quantitative /
scientific geography have come and (mostly)
gone; contemporary critiques emphasizing con-
textuality and contingency are with us now. Also,
the human aspects of geography (in human geog-
raphy per se and in the inclusion of human
40 Volume 56, Number 1, February 2004

agency in much of physical geography) provide
a prototype for dealing with uniqueness and
irreducible unpredictability. While we know
that no two people are alike and that individual
behavior is unpredictable, we also know that
there is some degree of predictability—and
some generalizations to be made and applied—
at an aggregate level or in a probabilistic sense.
Perhaps similar reasoning can be applied to
other entities: no two ecosystems, streams, mid-
latitude cyclones, and so on are exactly the same,
and individuals have idiosyncracies, but predic-
tability may be pursued at an aggregate or pro-
babilistic level.
Similarly, synoptic climatology is a useful
prototype. Synoptic analysis is informed and
constrained by laws of atmospheric physics
and chemistry, but it implicitly recognizes
the idiosyncratic nature of air masses, pressure
systems, and weather maps. Developing typo-
logies based on geographical (regional) and
temporal (seasonal) contexts, makes predictions
possible. Again, the synoptic approach might
prove applicable to other problems, such as arid-
zone hydrology and runoff production (Kni-
ghton and Nanson 2001; Slattery, Gares, and
Phillips forthcoming).
The integration of law-based and contingent
methods depends to a large extent on spatial
analysis, as accounting for the effects of local
factors involves describing and explaining spa-
tial variability. Quantitative geography has wit-
nessed a shift from an emphasis from attempts
to derive global laws to an explicit recognition
of contingencies (Fotheringham and Brunsdon
1999). Rather than search for singular under-
lying governing laws, quantitative geographers
are now more likely to be attempting to explain
spatial variability, often incorporating spatial
statistics that explicitly account for location-
al particularities (Fotheringham and Brunsdon
1999). This paradigm has long held sway in
certain areas of physical geography, such as
landscape ecology and pedometrics, where ex-
plaining the nature of spatial variability has been
more prominent than attempts to uncover gene-
ral laws and where spatial patterns are typically
viewed as emerging from complex interactions,
rather than being imposed by a single dominant
control (Kupfer 1995; Webster 2000).
Finally, Reginald Golledge (2002) has done
an exemplary job of teasing out just those parti-
cular skills, abilities, analytical tools, and rea-
soning for which geography is well suited and
with which geographers tend to be dispropor-
tionately blessed. Some of these—for exam-
ple, place-based reasoning—are inherently well
suited to the synthesis of nomothetics and
idiographics.
Summary and Alternative Visions
The future of physical geography, like that
of most other fields, will be characterized by
irreversible divergence and intellectual niche
specialization. This is likely to lead to fractiona-
tion and decomposition of common bodies of
knowledge and core epistemologies. This dete-
rioration of common frames of reference is the
biggest challenge that fragmentation and spe-
cialization pose to the practice—as opposed to
the institutions—of physical geography.
Technological innovation has revolutioni-
zed physical geography, and the availability of
measurement techniques is no longer the major
limitation to advances in the science of physical
geography. As new technology is increasing-
ly brought to bear on classic and chronic pro-
blems, future progress will be determined by
our ability to conceive new, interesting, and
important problems.
We may also be approaching the limits of
what can be accomplished via traditional metho-
dological approaches to the study of human-
altered environments. Further progress will
depend on research that is able to incorporate
both biophysical and human (social, cultural,
economic)processes at high—and comparable—
levels of theoretical and analytical sophistication.
Finally, the future calls for science in general,
and earth and environmental science in par-
ticular, to embrace and confront the creative
tension between nomothetic and interpretive
science and to fruitfully and explicitly integrate
these approaches. More than any other (sub)-
discipline, physical geography is both crucially
affected by this synthesis and well positioned to
contribute to it.
Based on the challenges outlined above, we
can articulate alternative visions for physical
geography. At worst, physical geography will
continue to forge ahead more slowly than might
otherwise be the case, as the decline of com-
mon frames of reference inhibits communica-
tion and leads to inefficiencies as old ground
is replowed. Cutting-edge research will be
Laws, Contingencies, Irreversible Divergence, and Physical Geography 41

technology-driven, providing ever-greater in-
sight into traditional questions and problems.
Understanding of human impacts on the envi-
ronment will progress incrementally as human
and physical geography proceed separately,
with only clumsy and cursory efforts to engage
theories and methods from both sides. Histor-
ical and spatial contingency will remain largely
unintegrated with law-based approaches.
At best, physical geography will race ahead.
We will find ways to maintain and build com-
mon cores of knowledge even as inevitable
fragmentation occurs. Research will be proble-
matized primarily from observations and theory
derived directly from ecosystems, landscapes,
climates, and so on, with evolving technologies
developed, adapted, or brought to bear on those
problems. We will proceed with understanding
of and engagement with realities such as, for
example, the fact that ecosystem restoration
goals have as much or more to do with cultural
values as with environmental factors, or that
water-resource economics is likely to influence
the flow of some streams more than precipita-
tion. And we will find new ways to integrate
nomothetic science with historical, interpretive
research in ways that preserve the information
and insight of both approaches.
This best-case scenario is based entirely on
the practice of physical geography as science
and scholarship, rather than on the institution-
al and disciplinary politics of geography and
geosciences. Political struggles will no doubt
occur, and physical geographers are no doubt ill
advised to ignore them. The trajectory of our
field, however, depends primarily and over-
whelmingly on the extent to which we produce
relevant, high-quality work that takes advantage
of the perspectives and skills of geographers.
The future is bright. How bright? That is up
to us.’
Notes
1
The guest editors beseeched me to provide some-
thing more in the way of suggestions on how to deal
with these issues, and their suggestions were reason-
able. I resisted simply because I could come up with
nothing original or insightful to say on this subject.
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JONATHAN PHILLIPS is a professor in the De-
partment of Geography at the University of Kentucky,
Lexington, KY 40506-0027. E-mail: jdp@uky.edu.
His core research interests are in fluvial, coastal, and
soil geomorphology, pedology, and hydrology. He
is particularly concerned with: the theory of earth sur-
face systems; the coevolution of landscapes, soils, and
ecosystems; the role of fluvial sediment storage
and transport in landscape evolution; and applications
of spatial analysis in the geosciences.
Laws, Contingencies, Irreversible Divergence, and Physical Geography 43