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B. GRINDE
HAPPINESS IN THE PERSPECTIVE OF
EVOLUTIONARY PSYCHOLOGY
(Received 4 December 2001; Accepted 28 August 2002)
ABSTRACT. The human capacity for positive and negative feelings is shaped by
the forces of evolution, thus the evolutionary perspective should be relevant to the
study of happiness. This paper attempts to identify the more pertinent innate qualities
of the human brain, and discusses how the evolutionary perspective can be used
to relate these qualities to the study of happiness. Two aspects of our evolutionary
legacy appear to be particularly relevant: One, the consequences of discords between
the present way of living and the environment of evolutionary adaptation; and two,
the presence of feelings designed to influence behaviour. The purpose of the present
paper is to both expand on these two aspects and thereby arrive at an evolutionary
based description of happiness; and to discuss the relationship between this biological
account and some current approached to the study of happiness.
KEY WORDS: evolutionary psychology, happiness, mismatches, discords, brain
rewards, environment of evolutionary adaptation, biological perspective.
In recent years the evolutionary, or biological, perspective has become
widely accepted as relevant input to the social sciences, as witnessed
by the emerging fields of evolutionary psychology and evolutionary
anthropology.1Whenever a feature, such as an emotion or a behav-
ioural pattern, is influenced by genetic constitution – that is, when it
involves innate tendencies – it is expected that an appreciation of human
evolutionary history will contribute to our understanding of that feature.
There are several lines of evidence backing the claim that happiness is
influenced by human genetic inheritance, including the cross-cultural
universality of concepts describing this state. In fact, the contention
may seem obvious, as it is generally recognised that there is a genetic
component to the human capacity for sensations and feelings, includ-
ing those related to mood. Consequently the study of happiness should
benefit from an understanding of the character of the relevant genetic
influence.
In the present article ‘happiness’ will be used in the meaning of ‘the
subjective appreciation of ones life-as-a-whole’. In other words, as to
Veenhoven’s (2000) division of aspects relevant for the quality of life
into a four-partite matrix, the present use of the term happiness covers
the ‘appreciation of life’ quadrant. Happiness, in the present meaning,
appears to be not so much a feature shaped explicitly by the evolutionary
process, but rather an indirect consequence of human nature; and as
Journal of Happiness Studies 3: 331–354, 2002.
© 2002 Kluwer Academic Publishers. Printed in the Netherlands.
332 B. GRINDE
such may be better referred to as a state of mind, rather than as a
trait. Although happiness is a rather abstract quality, the various meth-
ods designed for measuring subjective well-being do presumably offer
relevant assessments.
It should be mentioned that not all cultures necessarily hold happi-
ness to be the main purpose of life, and certainly not the main mea-
sure of success. For example, in Asian collectivist cultures following
the norms of society is apparently considered more important than are
personal feelings (Suh et al., 1998). However, as far as the present
model of happiness is concerned, it is not important whether the posi-
tive mood of the individual is a consequence of success in following the
norms of society, or results from a more direct approach to the pursuit
of happiness.
As pointed out elsewhere, the main contribution of the evolutionary
perspective in understanding human emotions and behaviour is to help
shape a broader view (Buss, 1998; Palmer and Palmer, 2001). Thus,
evolutionary psychology may be of limited value in regard to practical
advice on how to study happiness, but could offer a useful conceptual
framework. Moreover, the evolutionary perspective is most suitable
for elucidating the general impact of the genes, thus although there is a
genetic component to the individual variation in the propensity to enjoy
life (Diener and Lucas, 1999; Lykken, 2000), this will not be an issue
in the present article.
There are actually two main links between the natural sciences and
the study of happiness: The evolutionary perspective and the neurolog-
ical approach. The discipline referred to as ‘affective neuroscience’
(Panksepp, 1998) covers pertinent knowledge regarding neurologi-
cal correlates of emotions, including those that may affect happiness;
and another recent book, edited by Kahneman et al. (1999), includes
chapters that look specifically at physiological–neurological aspects of
well-being. The present paper concentrates on the evolutionary per-
spective. Previous work in this field (Grinde, 1996; Barkow, 1997;
Buss, 2000) points towards two lines of reasoning: The relevance of
the environment, and the relevance of sensations. The following dis-
cussion will start by expanding on these two perspectives, followed
by an attempt to formulate a biological description of happiness; and,
finally, a discussion on how this description relates to current studies of
happiness.
HAPPINESS IN EVOLUTIONARY PSYCHOLOGY 333
THE ENVIRONMENT
In biology, the concepts most closely related to quality of life are
‘fitness’ and ‘success’. The key to obtaining reproductive success lies
in a combination of fitness and an appropriate environment, where the
term ‘environment’ embraces both physical and social aspects. The
‘appropriateness’ of the environment is a question of to what extent it
caters to the genetic constitution of the organism.
Human genes are designed for particular conditions of living, as are
the genes of any organism, but in the case of humans (and presumably
other mammals) the advantage of a suitable environment is not solely a
question of allowing for reproductive success: A proper environment,
as will be argued, correlates with an improved mental state. The point
is substantiated by research on animals, which indicates that living
under unnatural conditions, whether in regard to physical or behav-
ioural aspects, has detrimental effects on health, including mental con-
stitution, and consequently a presumed negative effect on the quality of
life in the sense referred to as happiness (Moberg, 1985; Lord, 2002).
Thus, whereas happiness is relevant for biological success only to the
extent that the state of mind influences fitness, the appropriateness of
the environment is relevant for happiness.
It may seem obvious that happiness is affected by having conditions
that cater to basic needs, but, as will be discussed below, the qual-
ity of the environment may also influence happiness in more subtle
ways. In other words, it is conceivable that minor deviations from the
conditions for which the genes have designed humans can have long-
term detrimental effects on the psyche. Moreover, which environmental
deviations that are likely to promote distress is not necessarily obvious.
Environment of Evolutionary Adaptation
The concept ‘Environment of Evolutionary Adaptation’, or EEA, has
been coined to reflect the conditions to which the genes are adapted.2
The human EEA is typically associated with the Middle or Upper
Palaeolithic environment of our ancestors; or, to phrase it differently, the
environment in the period following the emergence of modern humans,
some two hundred thousand years ago. The first change towards a dif-
ferent environment – one less in tune with the genes – presumably
came with the increase in group size and beginning of agriculture
10 000–15 000 years ago.
334 B. GRINDE
It should be noted that human genes were not shaped in one particular
environment, but rather over millions of years of interaction with vari-
ous conditions. Our basic emotions, for example, did not appear in the
Stone Age, but entered the brains of our ancestral animals some hundred
million years ago, as evidenced from the observation that related emo-
tional structures are present in brains of animals that parted with our
lineage that long ago (Panksepp, 1998). Subsequent evolution, all the
way up to modern humans, modified the emotional dispositions, but
the alterations had to comply with the rules governing the evolutionary
process, and as such do not necessarily reflect perfect adaptations to
the particular conditions of Palaeolithic tribes.
One may also point out that present humans are adapted to diverse
environments: The Inuits of Greenland are adapted to a different climate
than the African Bantus. However, these variations in climatic adap-
tation may not matter that much for the present discussion – the more
pertinent features of human EEA are presumably not so much a mat-
ter of the physical environment, but rather a question of social envi-
ronment. Although traditional societies are organised in a variety of
ways, the genes that influence social inclinations have probably not
diverged significantly. This contention is supported by the observation
that, compared to other species for which there are relevant data, the
human species is genetically homogenous (Kaessmann et al., 2001).
To conclude so far, with the above limitations in mind, it may still
be convenient to consider the way of life of Palaeolithic tribes to be an
approximation of a universal human EEA, at least as far as social and
behavioural adaptations are concerned. However, we obviously only
have scant indirect evidence as to the nature of the environment and
way of life at that time.
The Concept of Discord
The disparities between how we live and what our genes are adapted to
have been referred to as ‘mismatches’.3The words ‘strain’ or ‘stress’
will here be used for the detrimental effects of living under subopti-
mal conditions; mismatches are presumably often associated with such
strain, but not always. For example, to sleep on a modern mattress prob-
ably creates less strain on your body than sleeping on the ground, and
having a door to lock reduces the stress associated with worrying about
predators. I shall use the term ‘discord’ for the cases were mismatches
have detrimental effects. Thus, while a mismatch may be beneficial,
HAPPINESS IN EVOLUTIONARY PSYCHOLOGY 335
a discord implies a situation that in some, if not most, people cause an
element of strain in a negative sense.
Some of the strain caused by discords is presumably associated
with the classical stress response. Excessive activation of this response
has been linked to a long list of ailments: Stress compromises the
immune system, it can induce complaints such as headaches and mus-
cle pain, and it is implicated in emotional problems such as depression,
nervousness, aggression, and social maladjustment.4As a ‘discord’ is
defined as being a deleterious mismatch, those discords that do not
cause problems related to the classical stress response, should never-
theless correlate with a reduction in happiness and health. As pointed
out above, a link between discords and health is well documented in
the case of animals.
Discord situations presumably troubled our Palaeolithic ancestors as
well, for instance when a natural catastrophe ruined the local environ-
ment, or when a child was orphaned. A discord situation is therefore
better defined as a deviation from appropriate, or optimal, conditions,
rather than a deviation from a particular environment that occurred
sometime in our evolutionary history. The main point is that happi-
ness is expected to correlate inversely with the presence of discords;
since they tend to disturb the delicately balanced human physiology.
As to their effect on the brain, a reasonable description would be to say
that they act like sand in the human emotional machinery. Although
humans appear to be more versatile than most animals, and certainly
sufficiently versatile to survive out of balance, we are not necessarily
versatile enough to avoid the cost of discords.
It is important to note that we are not necessarily aware of to what
extent the conditions we live in are permeated with discords, neither
do we know what sort of detrimental consequences the discords may
generate. An example from anatomy illustrates the point: Myopia is
closely associated with life in industrialised societies (Curtin, 1988).
The increased incidence of myopia is presumably due to environmental
factors; both the tendency of infants to spend long periods focusing at
something very close (e.g., reading books), as well as exposure to light
during night-time early in life (keeping the lights on in the bedroom),
have been suggested as possible culprits (Widdows, 1990; Quinn et al.,
1999). The point is that the growth of eyeballs and lenses is affected
by their interaction with the environment, which means the quality and
timing of light, as well as the use of the muscles involved in focussing.
336 B. GRINDE
Human genes are adapted neither to books nor to electricity, and as a
consequence the expansion of the eyeball may end up not matching the
shape of the lens.
The genes have designed both physical features such as eyes, and
mental functions such as emotional dispositions, to mature with age; but
in both cases correct maturation relies on appropriate external stimuli.
As in the example of myopia, the mind may be ‘scarred’ or ‘burned’
by a variety of discord conditions without any recognition that the
conditions are actually harmful.5
It is generally agreed that gross discords, such as bringing up infants
without proper parental care, or in obviously deprived environments,
can cause problems that affect health (Lundberg, 1993; Shonkoff and
Phillips, 2000). It seems likely that less obvious discords may have
an impact as well, both in relation to the maturation of emotions, and
in the context of the mental constitution of adults. Possible examples
of more subtle discords include the amount of skin to skin contact,
the large number of strangers we interact with, restrictions on play
behaviour (particularly on ‘rough-and-tumble’ play), and sleep patterns
associated with shift work.
As a rule of thumb, one would expect that discords are particularly
problematic in relation to complex features, and in relation to features
that carry intrinsic weaknesses of design. In such cases it presumably
requires less of a discord to cause overt problems. The brain is certainly
a highly complex feature; furthermore, some of the ‘modules’ of the
brain may have a particularly fragile design.
Our innate stress-reaction is one possible example of a vulnerable
feature. All mammals react in a particular way to stressors (such as a
predator or an hostile opponent), however, humans are apparently par-
ticularly prone to turn this response into a harmful chronic stress state,
presumably because our recently evolved cognitive capacity allows us
to worry about all sorts of real or imagined ‘dangers’ (Sapolsky, 1999).
Thus the human stress-response may exemplify a weakness of design,
within the context of a highly complex organ. The prevalence of mental
problems related to anxiety and worry may reflect the effect of discord
conditions on this particular feature. The discord could, for example,
be related to an observation made by Liu et al. (1997) in rats. If rat
mothers lick their offspring often, the pups produce less corticotrophin-
releasing hormone (CRH, the master hormone of the stress response);
and, more importantly, the effect lasts: The amount of CRH produced
HAPPINESS IN EVOLUTIONARY PSYCHOLOGY 337
in the hypothalamus of the adult depends on the amount of licking
received during the first 10 days of life. In other words, a reduction in
the physical contact between parents and child can cause the child to
become more vulnerable to stress later in life.
While the science of ‘Darwinian medicine’ (Nesse and Williams,
1996; Trevathan et al., 1999) addresses the medical consequences of
discord situations, like the example of myopia, the present paper adopts
a broader view: Rather than restricting the discussion to overt health
problems, it includes the possible consequences of discord situations
on happiness. The pertinent question is whether the environment is
optimal for avoiding mental agony and fostering happy people; or
whether happiness is reduced by minor, possibly unrecognised, discord
situations.
POSITIVE AND NEGATIVE SENSATIONS
Evolutionary Stages Towards a Happiness Centred Species
In humans, evolution has created a species highly concerned with emo-
tional well-being, and with a potential for considerable variations in
mood, thus happiness possibly means more to our species than to any
other animal. Below are listed the four main evolutionary stages related
to the moulding of this property. The list is relevant because it puts
the existence of feelings, and thereby the propensity for hedonistic
pleasure, in a perspective.
1. The emergence of a nervous system
All organisms respond to environmental stimuli, but only in those
carrying nerves organised in ganglia (e.g., nematodes and arthro-
pods) or a centralised brain (vertebrates) can the response include
anything remotely resembling feelings. Flowers may thrive, but they
lack the nerve circuits required to appreciate the difference between
blooming and withering.
2. The use of measures that can be referred to as ‘rewards’ and
‘punishment’ in order to influence behaviour
The neurotransmitters normally associated with brain rewards (such
as opioids and dopamine) are present in all vertebrates, as well
as in many invertebrates, but they may not have been involved
in positive and negative sensations prior to the vertebrate stage
(Stefano et al., 1998; Panksepp, 1998). Vertebrates, however, are
338 B. GRINDE
presumably equipped with sensations designed to induce them to
behave – that is, to take actions – conducive to the propagation
of their genes. Generally, the behaviour is either of the ‘make-
the-best-of-an-opportunity’ type or ‘avoid-something’ type; which
roughly corresponds to positive and negative sensations (Nesse and
Williams, 1996).
3. The awareness of pleasant and unpleasant sensations
Although all vertebrates presumably ‘feel’ the difference between
positive and negative sensations, at least they respond accordingly,
the lower vertebrates are not necessarily ‘aware of’ pleasure or dis-
pleasure. There are data suggesting that this awareness evolved
between the amphibian and reptile stage of vertebrate evolution:
A reptile seeks pleasurable stimuli, such as sunbathing; and it is
actually possible to measure a physiological response in the sun-
bathing reptile akin to what can be measured in humans who engage
in positive experiences (Cabanac, 1999). Fish and amphibians do
not show the same physiological response, their behaviour is pre-
sumably more instinctive and less influenced by an appraisal of
sensations.
4. The evolution of self-consciousness and a concomitant increased
emphasis on feelings
Apparently only a few species have an awareness of a ‘self’.
According to the ‘mirror test’, and related tests, the list includes
humans, certain apes, and possibly some cetaceans (Gallup, 1997;
Reiss and Marino, 2001). Although sensations referred to as plea-
sure or displeasure do not necessarily depend on self-awareness,
this capacity presumably increases the importance of feelings.
Humans probably have conscious access to a larger fraction of brain
processes than other animals, and subsequently more capacity to
reflect on personal experiences; as a consequence, we may be more
tuned towards positive sensations.
It is tempting to speculate that positive and negative sensations have
a greater impact on the adaptation of humans than they have on any
other species. Not only has the capacity for self-awareness presumably
evolved further in humans than in other animals, and, as a consequence,
we have more conscious appraisal of how we are doing. Another effect
of consciousness is a greater measure of ‘free will’, and, for the genes,
free will is a two-edged sword: While an ant will always follow the
‘will of the genes’, a human may choose to take actions that are not
HAPPINESS IN EVOLUTIONARY PSYCHOLOGY 339
in the interest of his or her genes. Thus, in order to retain a genetic
influence on behaviour, it seems likely that evolution would enhance
the intensity of agreeable and punishing sensations.
Although the dichotomy of positive and negative sensations is a
simplification, when studying happiness it seems useful to consider
sensations as either rewarding or punishing. As noted above, the two
represent contrasting evolutionary purposes: Reward circuits are pre-
sumably designed as incitement, while penalising feelings function as
discouragement. The distinction is obvious in the case of the more
overt experiences; for example, the pleasures associated with food and
sex signal biological advantages, while the pain of burning a finger
is there to teach avoidance. It may be pertinent, however, to protest
against the notion that all sensations can be labelled as either positive
or negative, but, at the least, it should be possible to categorise the
aspects of human affective experiences that have the more obvious
impact on well-being.
It should be emphasised that the term ‘reward’ is here used for any
sensation considered to be agreeable, neurologists often use ‘brain
reward’ (sometimes referred to as pleasure drives) in a more specific
sense: The activation of particular nerve circuits involved in deliv-
ering the more distinctive pleasurable sensations (Panksepp, 1998;
Spanagel and Weiss, 1999). The ‘brain rewards’ are presumably associ-
ated with two discrete modules of the brain; one, typically referred to as
‘wanting’, serves the purpose of wetting the appetite and to energise the
mind and body towards exploiting a resource; while the other, termed
‘liking’ or consummation-associated pleasure, concerns the sensations
associated with the actual consumption (Robinson and Berridge, 1993).
There is considerable knowledge as to the neurochemistry and neu-
roanatomy of these two modules, and as to the neurology of pain,
while less is known about the mechanisms of pleasant and unpleasant
sensations associated with various less defined emotive states (for a
review see Panksepp, 1998).
Refinement of the Reward/Punishment Concept
The pertinence of rewards and punishment to the happiness of an indi-
vidual may seem obvious, but on closer examination it raises a number
of issues that need to be considered. Three such issues are singled out
below. For the following discussion, it should be kept in mind that evo-
lution shaped the human brain as a tool for survival and procreation,
340 B. GRINDE
feelings are consequently designed to promote appropriate behaviour
that sustains life, not to make life more pleasant.
The Relevance of Conscious Appraisal
In order to understand how feelings are perceived, it is important to look
at the relationship between conscious and unconscious processes in the
brain. Processes belonging to the unconscious part of the brain may
influence mood; for example, anxiety can be induced as a response to
stimuli the individual is not at all aware of receiving (Hallowell, 1998).
In fact, most feelings presumably start out in the basal, or unconscious,
parts of the brain, but to experience them requires an involvement of
cognitive functions. Whether feelings such as hunger and fear are con-
ceived as pleasant or unpleasant depends on the processing at this higher
level, and the outcome of the processing depends on several factors
such as past experiences, personality, and expectations. Thus, closely
related situations may sometimes be considered rewarding, while at
other times they may be experienced as punishing.
I shall exemplify this issue by taking a closer look at fear and
hunger. A dangerous situation can rapidly switch from a positive thrill
to a frightening encounter, as when a rock climber looses his grip. In
other words, fear can turn out as either rewarding or punishing. This
may seem like an inconsistency, but it makes evolutionary sense when
analysed in more detail. A scare is typically perceived as pleasant if
the individual retains control of the situation, while unpleasant if the
situation gets out of control, because these two modes of experienc-
ing fright serve different biological purposes: The brain is designed
to induce us to take some chances, otherwise we would never have
laid down a large prey or ventured into uncharted land; but it is also
designed to stop us from causing harm to ourselves, that is, to avoid
hazards. The ‘adrenaline kick’ associated with climbing a mountain or
riding a roller coaster may feel good, presumably because it improves
the chance of survival if voluntarily encountered dangerous situations
induce a positive mood and a high self-esteem. At the moment one
looses the grip on the mountain, the unpleasant sensations devoted to
harm avoidance kicks in.
Similarly, slight hunger can be experienced as pleasant; it entails
an anticipation of food-related rewards, and can intensify the pleasure
of eating. Too much hunger, however, is unpleasant, particularly in a
situation where no food is available. The displeasure of starving is there
HAPPINESS IN EVOLUTIONARY PSYCHOLOGY 341
to discourage the individual from ending up in the latter situation. In the
case of both fear and hunger it is presumably the conscious appraisal
of the situation that decides whether the deeper signals, of respectively
danger and lack of nutrients, give rise to agreeable or disagreeable
sensations.
Rewards Associated with Hapless Situations
Not only is the categorisation of sensations as either positive or negative
a simplification, in many cases the appropriate category is not at all
obvious. I propose that certain sensations that are intuitively classified
as negative actually contain an element of reward. For example, most
people will list sadness and grief as disapproving, yet they are often
actively pursued, as witnessed by the popularity of movies that induce
these emotions in the spectator.
As in the example of fear, in order to understand this apparent para-
dox it is important to look at the functional significance of sadness and
grief. One must distinguish between a harmful event and the associ-
ated response; the former is something to be avoided, the latter is a
natural reaction. The loss of a spouse may be tragic for the genes, but
as misfortunes occasionally occur, the genes have prepared the brain
to cope with the problem. The genes are best served by implementing
a mechanism that helps the survivor master the situation, and the nor-
mal response includes sorrow. The response may elicit compassion and
help; it may also improve mental recovery, and thus increase the chance
of finding a new spouse. The pertinent point is that to the extent grief
is adaptive, the brain should encourage this feeling; and the available
encouragement is in the form of an agreeable sensation. A beneficial
emotion should, at the least, not trigger disagreeable feelings.
The above example reflects the following rule of thumb: Engaging
the mind and body in tasks for which they are designed is expected
to promote happiness by instigating positive feelings. This principle
obviously applies to life-supporting actions, such as consuming food
or keeping warm, but it should also apply to situations of fear and
bereavement.
A situation of grief thus typically involves both negative and positive
elements, the negative ones are there to induce the individual to avoid
the unfortunate situation, and the positive ones are there to help the
individual make the best of the situation once it has occurred. When
watching a film, it is possible to nurture the positive effect; the spectator
342 B. GRINDE
can identify with – or empathise with – the characters, and enjoy sorrow
without personally having to go through the harmful event.
A similar argument can be made for physical pain: The sensation
is there to signal that you are hurting yourself, however, if you should
hurt yourself there is no reason to suppress the natural response, such
as screaming. Again, the point is to distinguish between, on the one
hand sensations (and concomitant behaviour) designed for aversion;
and, on the other hand, emotions involved in coping. According to
the present vocabulary, the former is a punishment, while the latter is
something the individual is urged to engage in, and is thus potentially
rewarding.
Long and Short-term Benefits
All mammals presumably have brains capable of experiencing plea-
sure, it is therefore not surprising to find that, when offered the oppor-
tunity, animals will indulge in stimuli that activate the relevant brain
circuits (Panksepp, 1998). Humans, however, are unique in that we
have the brainpower to understand and exploit the situation; not only
can we procure large quantities of naturally occurring rewarding stim-
uli, we have also created a number of substitutes, such as narcotics,
artificial sweeteners, and pornography.
Most of the commercial stimulants can have negative consequences.
The health effects of excessive use of stimulants such as sweets, fat
food, and narcotics are well known. There are three main obstacles to
having the long-term effect of indulgence in stimulants ending up as an
overall positive effect on happiness: One, the long-term consequences
may jeopardise health, which will reduce the subjective enjoyment of
life; two, the reward tends to diminish with habituation, in fact, even
short-term stimulation typically leads to hedonic adaptation (Frederick
and Loewenstein, 1999); and three, the life situation created is not
natural and may therefore involve an element of strain in the present
sense.
Reward mechanisms evolved under conditions where the possibil-
ity of abuse was negligible. If misuse had been a problem (that is,
if the stimuli were so easily available that overindulgence commonly
decreased fitness) one would expect the process of evolution to eventu-
ally change the brain in a way that counteracted abuse. Thus for animals
living under natural conditions, reward mechanisms presumably func-
tion according to the purpose; while if a species suddenly finds itself
HAPPINESS IN EVOLUTIONARY PSYCHOLOGY 343
in a situation of abundance to which it is not adapted, such as humans
in an affluent society, there are likely to be complications. In other
words, when including rewarding sensations as a component of hap-
piness, it is important to balance short-term benefits against long-term
disadvantages.
THE BIOLOGY OF HAPPINESS
A Biological Description of Happiness
Based on the above discussion, it is possible to formulate a model for
understanding happiness in an evolutionary perspective. This model
suggests that happiness is linked to two key concepts: One, to avoid
discord situations, and the concomitant strain, by adjusting the condi-
tions of life to innate tendencies; and two, to utilise the brain’s potential
for rewarding sensations. Thus happiness (in a biological sense) should
correlate with how successful the individual is in pursuing these princi-
ples. A related description has previously been referred to as ‘Darwinian
happiness’ (Grinde, 1996).
Refining the Biological Description: A Default State of
Positive Mood
The above description distinguishes between ‘avoiding strain’ and
‘obtaining rewards’. There is no distinct line separating these two prin-
ciples; as previously pointed out, positive feelings are expected to arise
when a person engage the mind and the body in tasks for which the
genes have designed them. In other words, behaviour and mental activ-
ity that are in tune with inherent tendencies will be supported by the
brain, and are thus expected to be pleasant.
Another point to be made is that the brain is obviously not always
in the course of harvesting an overt reward or enduring a punishment.
Although it may be argued that the mind tends to incline towards either
a positive or a negative mood, the more tangible feelings occupy the
mind for only a fraction of the day. On the other hand, some moods
can permeate the day; either in a negative sense such as anxiety, or a
positive sense such as love. Yet, even in the absence of blatant rewards,
and in the absence of a permeating mood, most people seem to sense
life as being more or less good. Presumably this subjective assess-
ment is to some extent a consequence of variations in innate qualities
344 B. GRINDE
(Diener and Lucas, 1999; Lykken, 2000), the present model argues
that it is also a consequence of how the individual relates to the above
biological description of happiness.
The concept of ‘default positive mood’ – that the human brain is
apparently designed to offer a positive frame of mind as long as the
situation does not dictate alternative moods – somehow blends the
principles of ‘strain avoidance’ and ‘reward harvesting’. In support of
this concept, several studies infer that, when basic needs are met, most
people enjoy life, and that people tend to be optimistic.6There is also an
argument favouring this notion based on the evolutionary perspective:
Evolution should prefer the basal state of mood to be agreeable as it
is presumably in the genes’ interest to reside within a content carrier;
a good mood is more likely to spur the individual to participate in
procreation and life-supporting functions, at least when compared to a
depressed state.
Moreover, while health is obviously important for happiness, it is
more difficult to evaluate to what extent a good mood can procure
health, or if a drop in happiness is solely a secondary consequence of
ailments. The idea that a positive mood can improve fitness, and thus
offer a biological advantage, is substantiated by a reported correlation
between positive emotions (as assessed by analysing autobiographic
texts written by nuns in early life) and longevity (Danner et al., 2001).
One investigation that might seem to contradict this study is the report
by Friedman et al. (1993). In a long-term follow up of persons whose
personalities were tested when they were children, they found that
longevity correlated with conscientiousness rather than cheerfulness;
but then the item referred to as cheerfulness in this study also correlated
with risk taking. In another analysis of the same data, Peterson et al.
(1998) found evidence for the expected inverse relationship between
pessimism and longevity.
Pain and negative moods are there for particular purposes, and as
long as the stimuli eliciting such feelings are avoided or dealt with the
general mood should be agreeable. Unfortunately, losing the state of
‘default positive mood’ may be one of the more typical consequences
of a discord life situation; and even the presence of ample reward-
eliciting stimuli may be insufficient to compensate for this deprivation.
A variety of techniques, such as various forms of meditation and yoga,
are presumably aimed at returning the individual to the default positive
mood, and at nurturing this state of mind.
HAPPINESS IN EVOLUTIONARY PSYCHOLOGY 345
HOW THE EVOLUTIONARY PERSPECTIVE RELATES TO
HAPPINESS RESEARCH
It is common to distinguish between conditions required for happi-
ness (alternatively referred to as opportunities for a good life), and
the actual sensation of well-being. McCall (1975), for example, makes
this distinction. In his view the feeling of happiness is linked to need-
gratification, and the conditions for happiness to the prerequisites for
this gratification to take place. It is relevant to note that, when making
this bipartite division, the quality of the social or physical conditions
are often added to the score of happiness. Thus, in the view of McCall,
beneficial conditions are of value, even if the individual does not exploit
the opportunities available.
Need-gratification is closely related to ‘rewards’ in the evolution-
ary perspective. In the present model, however, the term ‘rewards’ is
probably used in a broader sense, as exemplified by the suggestion that
even emotions such as grief can contain an element of reward. The
‘conditions required’ are related to the present emphasis on ‘discords’.
However, discord situations can occur even if all apparent needs are
gratified, thus the concept of discord may cover more territory than
what is intuitively included in a list of conditions required for happi-
ness. For example, in the present model minor disturbances caused by
discord conditions during infancy can have long-term effects on quality
of life, even if these conditions are not recognised in the least as being
adverse, and even if the adult environment is optimal. Moreover, in the
present model, the environment itself is not part of the happiness score,
only the impact it has on the actual well-being of the individual.
The relevance of the term ‘biophilia’ (Kellert and Wilson, 1993) to
research on happiness (Gullone, 2000), is also related to the concept
of discords. Work along this line suggests an increase in well-being
upon exposure to natural features of the environment, as well as pos-
sible adverse outcomes related to life in environments that contrast
our EEA. There are, for example, data indicating that humans thrive
better, and improve in cognitive tasks, in the presence of plants.7The
typical city environment, where concrete dominates, as opposed to an
organic environment with ample vegetation, could exemplify the subtle
discords that may exert a negative impact on the human mind.
The previously mentioned model proposed by Veenhoven (2000)
expands on the above bipartite distinction by subdividing the
346 B. GRINDE
‘conditions for happiness’ into ‘outer qualities’ and ‘inner qualities’,
and by adding an ‘outer quality’ entity to the gratification part.
Veenhoven’s four-partite model seems to cover most, if not all, aspects
embraced by other models. The conditions required for happiness are
divided into the ‘livability of the environment’ (the external part), and
the ‘life-ability of the person’ (the internal part). The former appears
to cover whatever aspects of the environment are relevant, and is thus
closely related to the concept of discords.
In ‘life-ability’ of a person lies the individual propensity to enjoy
life. Some people are more prone to suffer from anxiety and depres-
sion, others tend to have a more cheerful disposition. The concept of
‘life-ability’ is related to what Lykken (2000) describes as a ‘set point
for happiness’, in the sense of more or less fixed individual differ-
ences in the propensity for experiencing positive and negative sensa-
tions. Life-ability reflects both innate and acquired attributes, where the
acquired component presumably is equivalent to the impact of discords
on the mind. In other words, the strain of discords adds a burden that
pushes people below their initial set point.
Veenhoven also divides the more overt aspects of life quality into
an external and an internal category; the former being referred to as
‘utility of life’ and the latter as ‘appreciation of life’. The ‘appreciation
of life’ category comes close to the general use of the term happiness,
and is thus the category more closely related to the use of ‘happiness’ in
the present evolutionary perspective. Discord conditions decrease the
propensity for happiness; brain rewards – in the present sense – add to
the measure of happiness.
The rationale for including ‘utility of life’, alternatively referred to as
‘external worth’ or ‘functionality for the environment’, in a description
of happiness seems less obvious; and, as pointed out by Veenhoven, this
aspect is absent from many of the proposed alternative descriptions. The
utility of life aspect is presumably most relevant where attention focuses
more on the quality of society, while the relevance seems less obvious
when the emphasis is on the happiness of the individual. However, the
importance for the individual of feeling useful, or finding a meaning
in life, is a recurrent theme in both psychological and philosophical
writings, and thus deserves an attempt at a biological explanation.
In the evolutionary perspective, the contribution to individual
happiness of having a ‘meaningful life’ is definitely relevant, but this
contribution is easily included in the present use of the word ‘reward’.
HAPPINESS IN EVOLUTIONARY PSYCHOLOGY 347
The perceived importance of utility (and the concomitant rewarding
sensations) is presumably related to two aspects of human biology:
One, humans are designed for gregarious social interactions, and the
propensity for positive sensations accompanying acts that benefit oth-
ers is included in that design (Grinde, 2000). For example, there are
rewards associated with the feeling of ‘helping comrades’, as well as
with being appreciated by others. Two, adult humans probably have
an internal drive mechanism towards utility, a propensity that may
have been a consequence of the increase in ‘free will’ – an organism
with a high level of free will requires more incentives towards actions
that promote the future of the genes. Thus acts perceived as useful,
whether for the benefit of others or oneself, should trigger positive
sensations.8
A variety of approaches to measure the quality of life have been
proposed. The bipartite distinction of the theoretical models is typi-
cally reflected in the suggested methods, most measures focus either
on the question of subjective well-being, or on the degree to which the
conditions for happiness are present, or on both of these qualities. The
subjective feeling of happiness, based on self-reporting, is necessarily
subjective, but to the extent that it can be trusted, of obvious relevance
to the actual quality of life of an individual. Apparently the current
approaches are sufficiently good to give meaningful results in terms
of validity and reliability (honesty of answers, interpersonal/cross-
cultural comparability, and interpretation of questions) (Veenhoven,
1996). I expect that the available subjective methods for assessing hap-
piness do offer relevant estimates regarding the present meaning of the
term as well.
The most important dispensers of rewards and punishment are pre-
sumably associated with the requirements for procreation and sus-
taining life: Sex, food, shelter, and health. If these basic needs are
satisfied, the most significant external factor appears to be our social
life. Consequently, typical inventories for assessing the conditions for
happiness emphasise health and social affiliation.
Much of the research on happiness has been in the direction of finding
factors in the society, and in the personality of individuals, that corre-
late with the score on happiness assessment scales. In a recent review,
Myers and Diener (1996) suggest four aspects of personality that corre-
late rather consistently with happiness. For one, extroverts are happier,
a finding that is presumably related to the strong correlates between
348 B. GRINDE
happiness and the quality of bonds with friends and family, where the
marriage bond appear to be particularly important (Veenhoven, 2001).
An alternative way of depicting the importance of affiliations is to look
at measures such as ‘social participation’ and ‘social support’. Humans
have evolved to a rare combination of pair-bonding and highly social
behaviour, and the biological ‘glue’ that sticks both the couples and the
tribe (or society) together is based on emotions. It should therefore not
be surprising to find that when the social aspects of life do not func-
tion satisfactorily, there will be an emotional burden and a concomitant
reduction of happiness.
As to two of the other personality correlates of Myers and Diener
(1996), liking oneself and optimism, it is tempting to suggest that these
traits may to some extent be a question of whether the individual has
been able to retain, or find, the default state of positive mood.
The fourth correlate reported by Myer and Diener (1996) is the sense
of ‘personal control of life’, a factor that is presumably closely related
to the importance for happiness of a ‘freedom’ (Veenhoven, 1996). It is
interesting to note that people indeed tend to be happier in societies that
treasure the freedom of the individual, compared to more collectivist or
confining regimes (Veenhoven, 1999). The possibility of taking charge
of ones life seems to be important, and societies that demand narrow
rules of conduct, obviously leave less room for personal independence.
In the tribal communities of our Stone Age ancestors, the social ties,
and the concomitant social participation and feelings of responsibil-
ity, were probably strong, but they were adapted to our measure of
innate gregariousness, and thus not felt to be confining or oppressive.
With the advance of large scale societies, there came a need to install
social obligations between people who did not have personal ties, the
typical solution was to use some form of authority to enforce princi-
ples of behaviour. The point is that while being considerate to those
you are emotionally attached to is natural and rewarding, and does
not require coercion, the enforcement of rules of conduct does limit
personal freedom, and thus reduce the feeling of control. A relevant
question is whether it is possible to induce the right types of emo-
tional bonds between individuals who do not grow up in the setting of
a close-knit tribe. Theoretically it may be possible for a society to have
the citizens retain a feeling of personal control, and at the same time
behave in a manner conducive to the best of the society – the question
is whether the innate gregarious emotions can be exploited to divert
HAPPINESS IN EVOLUTIONARY PSYCHOLOGY 349
people towards behaviour, that is, for the good of the community, and
thus allow societies to rely less on authority.
The concept of flow – the optimal experience – as described by
Csikszentmihalyi (1991) is presumably related to the notions of rewards
and a positive default mood. To obtain the experience of ‘flow’ a person
should engage himself, to the extent that he may be totally absorbed,
in tasks that appear meaningful. In the evolutionary perspective this
seems to be related to the previously made statement that behaviour
and mental activity that are in tune with inherent tendencies will be
supported by the brain, and are thus expected to be pleasant. Moreover,
to keep the mind engaged in this way may also help the individual avoid
discords.
CONCLUDING REMARKS
While it is relevant to consider the quality of life of any organism in
the meaning of biological success, ‘happiness’ is a term that applies
primarily or exclusively to higher vertebrates, and to man in particular.
The purpose of the present exercise has been to offer a contribution to
a discussion of what the biological correlates to happiness may be.
Applying an evolutionary perspective to the social sciences is some-
what controversial, one relevant concern is that this perspective sug-
gests a too deterministic model, another is that the conclusions can
be misused.9For example, regarding the present application of evo-
lutionary thinking, the idea that stimulation of brain rewards adds to
happiness could be taken to suggest that any means to obtain these
sensations are warranted. Besides the concern for long-term negative
consequences, there is the obvious fact that the pursuit of happiness
for one person is sometimes in conflict with what is good for others.
Both concerns are pertinent; the response should be to add necessary
qualifiers.
The present evolutionary perspective suggests three approaches that
are relevant in order to understand the nature of happiness: The first
is the question of the quality of the environment, where the principle
of ‘discord avoidance’ is not necessarily that far from Veenhoven’s
(2000) concept of ‘livability of environment’. However, the line of
reasoning is somewhat different, and, in the present description, the
part of the ‘life-ability’ of a person that is not due to innate factors
350 B. GRINDE
may be included as consequences of the environment. The second is
the emphasis on positive sensations, here referred to as ‘rewards’ in
the brain. The content of this concept is presumably related to previous
entities such as ‘need gratification’, but again the theoretical rationale
is quite different. The third approach is to suggest that, in a healthy
individual who has managed to avoid disabling discords, the expected
frame of mind has a positive tone, here referred to as a ‘default positive
mood’. The latter idea is related to the observation that people tend to
be optimistic and positive (Myers and Diener, 1996; Lykken, 2000).
Happiness should not be conceived as a distinct trait or ‘unit of
evolutionary strategy’. The observed variation in well-being, indeed
the fact that the concept of ‘happiness’ is part of the human vocabulary,
is presumably an indirect consequence of how humans are equipped
with sensations that help direct behaviour towards what is evolutionary
viable, as well as with our particular form of consciousness and the
concomitant capacity for appraisal of feelings. Thus one should not
expect to find a module for happiness in the brain, but accept that good
feelings are a consequence of the aggregate of a large variety of brain
activities. Discords cause a reduction in happiness presumably because
they reduce the likelihood that this aggregate of activity yields positive
sensations, either through immediate effects or long-term effects. In
other words, discords probably tend to disrupt the default setting by
corrupting emotional parts of the brain.
Leaving aside innate individual variations in propensities for happi-
ness, according to the present model those who score best on happiness
are those who avoid discord conditions, and thereby manage to retain
their default positive mood, and who are as a consequence in the best
position to delight in the rewarding sensations associated with han-
dling the daily chores of life. One question that derive from the present
model, and that may be approached in future research, is whether the
national and cultural variations in happiness scores (Veenhoven, 1999;
Diener and Suh, 1999) can be related to the extent of discords in the
societies being compared.
NOTES
1The recent interest in the evolutionary perspective is reflected in several books,
for example, Buss (1998), Cronk et al. (2000), and Palmer and Palmer (2001).
2Check Crawford and Krebs (1997), and references therein, for a discussion of EEA.
HAPPINESS IN EVOLUTIONARY PSYCHOLOGY 351
3The concept of ‘mismatch’ has been deliberated by Eaton et al. (1988), and Pani
(2000).
4Several books review the effect of stress on mental and physical health problems;
for example, Carroll (1992) and Sternberg (2000).
5For a treatise of how various conscious or unconscious events can leave ‘burns’
in the brain, see Hallowell (1998).
6The predominance of happiness is discussed by Veenhoven (1997). Myers and
Diener (1996) include a discussion on optimism.
7Data presented at the International Society for Human Ethology (ISHE) meet-
ing in Salamanca 2000 by E. Oberzaucher and K. Grammer (abstracts available at
http://evolution.humb.univie.ac.at/events/salamanca-abs.html).
8For a discussion of leisure and the need to do something ‘useful’, see Parker (1976).
9See Segerstrale (2000) for a discussion on the pitfalls and advantages of
‘sociobiology’.
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Address for Correspondence:
B. GRINDE
Norwegian Institute of Public Health
P.O. Box 4404
Nydalen 0403
Oslo, Norway
E-mail: bjorn.grinde@fhi.no
