GET DARWIN OUT OF YOUR BRAIN
by
BERNARD CRESPI
__________________________________________________
Bernard
Crespi is Professor of Evolutionary Biology at Simon Fraser
University.
Evolutionary
psychology, like sociobiology or Marxism, has become associated
with controversy. Why should it, and why has it? Yes, debates
about evolution totter endlessly along, and psychology remains
a discipline that sometimes seems orphaned by both humanities
and the hard sciences. Why should combining psychology and evolution
ignite a confabulation of loathing, fear, and scientific vitriol?
First,
not only do we (here, a royal ‘we’ of evolutionary
biologists like myself) expect very many people to not understand
evolution, because it is too simple and mechanistic for our
meaning-laden world; we also predict that people should reject
evolution because one of its core provisos is that people, you
and me, should generally behave so as to maximize their relative
fitness. Competition, survival, reproduction, of the fittest?
Not me, you? For shame. Evolutionary theory indeed predicts
that we should each believe, or at least rationalize, ourselves
to be mutualistic, altruistic and moral nearly to a fault, because
that is one of the best ways to get the edge on, or into, our
competitors, be they individuals or other groups. So are you
a believer now? Evolution is controversial because its very
existence seems to attack our core beliefs about our own goodness
and the biggest questions regarding human purpose.
Second,
psychology purports to study the brain, but can it do so scientifically,
like other disciplines? Will generating questionnaires, and
treating humans in modern, novel environments like lab rats,
illuminate the inner-workings of the most complicated known
structure in our universe? The hard sciences are hard because
they are reductionistic – they infer mechanisms, processes,
parts that, combined together, explain the workings of whole
systems. They conduct controlled, predictive experiments. They
have conceptual frameworks built from math and data, not fashion.
So armed, they ratchet forward, fact by incontrovertible fact.
‘Soft’ disciplines are soft because they reject
reduction, and indeed often claim post-modern relativity for
all. Psychology is a soft science because it cannot reduce –
there is no place to go except neuroscience, which would swallow
it up with nary a belch, given the chance. Evolutionary biology
is historical but also reductionist, in that it specifies the
precise set of processes whereby all phenotypes have come to
be, and change, and it tells us how to discover what functions
they serve. As such, it illuminates all domains of science,
from genetic sequence through to human behaviour – or
at least would, if allowed to by academic practitioners. Psychology
is controversial because it is a soft science trying to answer
the hardest of question, how the brain works. It can’t.
Third,
evolutionary psychology was forged in a crucible of polemic,
as specific schools of thought, such as the school of highly-modular
fitness-increasing brain functions developed by Leda Cosmides
and John Tooby. These researchers staked out strong claims,
trained talented students, and attacked intellectually-neighbouring
tribes. Adopting one side of polarized viewpoints, and sticking
to it, remains a highly-effective route to scientific notoriety,
even though in almost all such fierce academic battles both
sides are partially correct, and both partially wrong. We are
a deeply tribal species, and we love observing, or joining in,
a good scrap. In this case, though, an entire emerging, integrative
field has become conflated with extreme views of how the mind
thinks, which has made for inviting targets but distracted from
the much more general usefulness of evolutionary thinking. Will
psychology eventually be torn asunder, like anthropology has
been into post-modern, anti-evolutionary ‘culturalists’
versus mainstream but human-centric and evolution-minded biologists?
Will economics? One can only hope.
Fourth,
‘psyche’ indeed means ‘soul,’ and for
psychologists, the hostile tribes of evolutionary biology threaten
to steal it away, and subsume their discipline in its mechanistic,
reductionist embrace. The irony here is that if there is any
discipline that has no soul – that is, no unifying conceptual
framework – it is psychology, which has flitted from one
arbitrary, more or less imaginary construct to the next since
Wilhelm Wundt began treating introspection as data. Of course
psychology has produced deeply fascinating insights over its
many years. Of course we need a top-down approach to understanding
how the brain works, to meet neuroscience inexorably burrowing
up from the bottom. But don’t we need a mind-set that
recognizes that the brain and mind have evolved, like finches
and opposable thumbs? Any discipline would fight like hell to
defend its very existence, or at least resist radical transformation
at the hands of competitors. Controversy indeed often leads
to scientific revolution, with casualties on both sides.
Evolutionary
psychology is like evolutionary anything: it is founded on a
way of thinking about how the world works, how it has come to
be, and how to understand it. It works by telling us what hypotheses
to test, what data to collect, and how to interpret our results.
The fires of controversy over this emerging field have generated
both heat and light, but better understanding of their sources
will, I think, help us to control the flames and put them to
better use.