I have taken the liberty of pasting in excerpts of a Scientific American
article. While the subject is a version of evolutionary psychology, I
believe that we may discern some of the problems inherent in relating
physiological data to what I view as essentially a cognitive function:
deliberating about and articulating values and assumptions regarding
aesthetics:
*Scientific American* has placed on their web site the article
"Evolution of the Mind: 4 Fallacies of Psychology: Some evolutionary
psychologists have made widely popularized claims about how the human
mind evolved, but other scholars argue that the grand claims lack solid
evidence" by David J. Buller.
Here are some excerpts:
[begin excerpts]
Charles Darwin wasted no time applying his theory of evolution to human
psychology, following On the Origin of Species (1859) with The Descent
of Man (1871) and The Expression of the Emotions in Man and Animals
(1872). Ever since, the issue hasn't been whether evolutionary theory
can illuminate the study of psychology but how it will do so. Still, a
concerted effort to explain how evolution has affected human behavior
began only in the 1970s with the emergence of sociobiology. The core
idea of sociobiology was simple: behavior has evolved under natural and
sexual selection (in response to competition for survival and
reproduction, respectively), just as organic form has. Sociobiology
thereby extended the study of adaptation to include human behavior.
In his 1985 critique of sociobiology, Vaulting Ambition, philosopher
Philip Kitcher noted that, whereas some sociobiology backed modest
claims with careful empirical research, the theoretical reach of the
dominant program greatly exceeded its evidential grasp. Kitcher called
this program "pop sociobiology" because it employed evolutionary
principles "to advance grand claims about human nature and human social
institutions" and was "deliberately designed to command popular attention."
Times have changed. Although some self-identified sociobiologists are
still around, the current fashion is evolutionary psychology.
Evolutionary psychology maintains that adaptation is to be found among
the psychological mechanisms that control behavior rather than among
behaviors themselves. But, as the old saw goes, the more things change,
the more they stay the same.
Although some work in evolutionary psychology backs modest claims with
careful empirical research, a dominant strain, pop evolutionary
psychology, or Pop EP, offers grand and encompassing claims about human
nature for popular consumption.
The most notable representatives of Pop EP are psychologists David M.
Buss (a professor at the University of Texas at Austin and author of The
Evolution of Desire and The Dangerous Passion) and Steven Pinker (a
professor at Harvard University whose books include How the Mind Works
and The Blank Slate). Their popular accounts are built on the
pioneering theoretical work of what is sometimes referred to as the
Santa Barbara school of evolutionary psychology, led by anthropologists
Donald Symons and John Tooby and psychologist Leda Cosmides, all at the
University of California, Santa Barbara.
According to Pop EP, "the human brain consists of a large collection of
functionally specialized computational devices that evolved to solve the
adaptive problems regularly encountered by our hunter-gatherer
ancestors" (from the Web site of the Center for Evolutionary Psychology
at U.C.S.B.). Just as evolution by natural and sexual selection has
endowed all humans with morphological adaptations such as hearts and
kidneys, Pop EP says, so it has endowed all humans with a set of
psychological adaptations, or "mental organs." These include
psychological mechanisms, or "functionally specialized computational
devices," for language, face recognition, spatial perception, tool use,
mate attraction and retention, parental care and a wide variety of
social relations, among other things. Collectively, these psychological
adaptations constitute a "universal human nature." Individual and
cultural differences are, by this account, the result of our common
nature responding to variable local circumstances, much as a computer
program's outputs vary as a function of its inputs. The notable
exceptions to this rule involve sex differences, which evolved because
males and females sometimes faced distinct adaptive problems.
Moreover, because complex adaptation is a very slow process, human
nature is designed for the hunter-gatherer lifestyle led by our
ancestors in the Pleistocene (the period from 1.8 million to 10,000
years ago). As Cosmides and Tooby colorfully say, "our modern skulls
house a Stone Age mind." Pop EP proposes to discover our universal
human nature by analyzing the adaptive problems our ancestors faced,
hypothesizing the psychological mechanisms that evolved to solve them
and then testing those hypotheses using standard-fare psychological
evidence, such as paper-and-pencil questionnaires. Pop EP claims that a
number of psychological adaptations have been discovered in this way,
including evolved sex differences in mate preferences (males prefer
nubility; females prefer nobility) and jealousy (men are more distressed
by a mate's sexual infidelity, women by emotional infidelity).
<snip>
Fallacy 1: Analysis of Pleistocene Adaptive Problems Yields Clues to the
Mind's Design
Tooby and Cosmides have argued that because we can be quite certain that
our Pleistocene ancestors had to, among other things, "select mates of
high reproductive value" and "induce potential mates to choose them," we
can also be sure that psychological adaptations evolved for solving
these problems. But efforts to identify the adaptive problems that
drove human psychological evolution confront a dilemma.
On the one horn, while it is true that our ancestors had to "induce
potential mates to choose them," for example, such a description is too
abstract to provide any clear indication of the nature of human
psychological adaptations. All species face the problem of attracting
mates. Male bowerbirds build ornately decorated bowers, male
hangingflies offer captured prey, and male sedge warblers sing a wide
repertoire of songs. Figuring out which strategies ancestral humans had
to use requires a much more precise description of the adaptive problem
for early humans.
More precise descriptions of the adaptive problems our ancestors faced,
however, get impaled by the other horn of the dilemma: these
descriptions are purely speculative, because we have little evidence of
the conditions under which early human evolution occurred. The
paleontological record provides a few clues about some aspects of early
human life, but it is largely silent regarding the social interactions
that would have been of principal importance in human psychological
evolution. Nor do extant hunter-gatherer populations provide many hints
about the social lives of our ancestors. Indeed, the lifestyles of
these groups vary considerably, even among those who live in the regions
of Africa populated by early humans.
Moreover, as biologist Richard Lewontin of Harvard has argued, the
adaptive problems faced by a species are not independent of its
characteristics and lifestyle. Tree bark contributes to the adaptive
problems faced by woodpeckers, but stones lying at the foot of a tree do
not. In contrast, for thrushes, which use stones to break snail shells,
the stones are part of the adaptive problems they face, whereas tree
bark is not. Similarly, our ancestors' motivational and cognitive
processes would have been selectively responsive to certain features of
the physical and social environments, and this selective responsiveness
would have determined which environmental factors affected human
evolution. So to identify the adaptive problems that shaped the human
mind, we need to know something about ancestral human psychology. But
we don't.
Finally, even if we could precisely identify the adaptive problems faced
by our ancestors throughout human evolutionary history, we still
couldn't infer much about the nature of human psychological adaptations.
S election builds solutions to adaptive problems by retaining
modifications to preexisting traits. Subsequent adaptation is always a
function of how preexisting traits were modifiable. To know how a
solution to an adaptive problem evolved, then, it is necessary to know
something about the preexisting trait that was recruited and modified to
solve the problem. Without knowledge of our ancestors' psychological
traits--which we don't have--we can't know how selection tinkered with
them to create the minds we now possess.
Fallacy 2: We Know, or Can Discover, Why Distinctively Human Traits Evolved
<snip>
Fallacy 3: "Our Modern Skulls House a Stone Age Mind"
<snip>
Fallacy 4: The Psychological Data Provide Clear Evidence for Pop EP
<snip>
Coda
Among Darwin's lasting legacies is our knowledge that the human mind
evolved by some adaptive process. After all, the human brain is even
more costly to run than an internal-combustion engine these days,
consuming 18 percent of the body's energy intake while constituting
merely 2 percent of its weight. We wouldn't have such an organ if it
hadn't performed some important adaptive functions in our evolutionary past.
The challenge for evolutionary psychology is to move from this general
