I read an article about a month ago in the December 2008 issue of the Scientific American magazine called “Evolution of the Mind: 4 Fallacies of Pop Evolutionary Psychology.” The article is a critique of a branch of theoretical psychology that employs evolution to explain human nature to lay audiences. Normally, I wouldn’t try to reference an article from Scientific American for this blog, but the pervasive influence of pop evolutionary psychology both in the general public’s ideas about evolution, and on my own thinking, is worth a closer look.
In essence, evolutionary psychology is founded on several assumptions:
1. We can know the psychology of our Stone Age ancestors
2. We can thereby figure out how distinctively human traits evolved
3. Our minds have not evolved much since the Stone Age
4. Standard psychological questionaires yield clear evidence of the adaptations
Upon such shaky grounds, an impressive grand narrative has taken root. And it is not so much that Pop EvoPsych is wrong, per se, but that the evidence for the claims made is starkly lacking and might be nigh impossible to “discover” at any point in the future.
Here’s a brief synopsis of the four fallacies the article centers around (from the captions in the original article):
FALLACY 1: Analysis of Pleistocene Adaptive Problems Yields Clues to the Mind’s Design
Pop EvoPysch Says: that analysis of the adaptive problems faced by our Stone Age ancestors, such as how to compete for mates and resources, yields clues to the mind’s design.
But: without knowledge of our ancestor’s psychological traits – information we don’t have – we can’t know how selection tinkered with these traits to create the minds we now have.
FALLACY 2: We Know, or Can Discover, Why Distinctively Human Traits Evolved
Pop EvoPsych Says: that we know or can discover why distinctively human traits such as language evolved
But: to discover why any trait evolved, we need to identify the adaptive functions it served among early humans for which we have little evidence.
FALLACY 3: “Our Modern Skulls House a Stone Age Mind”
Pop EvoPsych Says: that modern people harbor a Stone Age mind
But: it seems just as likely that the human mind had to adapt to dramatic changes brought about by the advent of agriculture and life in cities. Humans have changed physiologically since the Stone Age, so why wouldn’t we have changed psychologically as well?
FALLACY 4: The Psychological Data Provide Clear Evidence for Pop EvoPsych
Pop EvoPsych Says: that the psychological data provide clear evidence for their claims, such as the differences in the basis of jealousy in males and females.
But: the data are largely based on forced-answer questionaires. Such evidence is inconclusive. It gives no clear basis, for example, for thinking that males and females evolved distinct mechanisms of jealousy. Instead both sexes may posses the same mechanism, which responds differently when faced with different types of threat to a relationship.
The main thrust of the article’s argument is that the evidence is lacking for many of the claims of Pop EvoPsych, and that the evidence required to substantiate those claims is most likely lost to us by the vast expanse of time that has elapsed since our Pleistocene ancestors walked the Earth. And while it is fun and/or intellectually stimulating to idly speculate about our ancestors’ psychological characteristics and the situiations for which those charactertistics may have evolved, to do so as though such musings are verifiable scientific facts is to invite prescriptions for dealing with modern psychological issues in potentially harmful ways. Because if we really don’t have a Stone Age mind inside our heads, what good can come from treating our psychology as such?
Until next time, bonnes pensées.