Our Mind is Not a Blank Slate: Evolutionary Psychologists Leda Cosmides & John Tooby

“Human behavior is the most amazingly flexible behavior of any animal species,” says UC Santa Barbara anthropology professor John Tooby, “but you can’t unlock these potentialities unless you understand the circuit logic or the code of the programs in the head.”

Reason TV’s Nick Gillespie recently sat down with Tooby and Leda Cosmides, a professor of psychology, who co-founded and co-direct the UCSB Center for Evolutionary Psychology. They believe their approach to examining the information-processing mechanisms that have evolved in the brain can provide greater insights into human behavior and cognition.

Tooby describes their work as being at the intersection of anthropology and primatology, evolutionary biology, and information theory and computer science. Cosmides says she starts with the idea that “behavior is generated by programs in your head, and I don’t mean it metaphorically—devices that are designed by natural selection to process information and guide your behavior. Evolutionary psychology focuses on that intermediate step of what’s the structure of those programs.”

Cosmides does not believe a true science of the mind is possible without an understanding of such structures, arguing that only such an approach makes it possible to intervene to improve people’s lives: “Just like being near-sighted doesn’t mean you can’t see—there’s glasses, contact lenses, there’s laser surgery. Why is that true? Because people bothered to figure out how the eye works.”

They push back forcefully against the criticism that an evolutionary approach is inherently racist or sexist, arguing that it deals with human universals. In fact, they believe their insights can unlock the best elements of human potential. Tooby cites as an example their success in getting people to stop implicitly categorizing others on the basis of race. The researchers hypothesized that this tendency was actually due to the modern co-opting of a cognitive program whose evolutionary function was to detect coalitions, so they crafted experiments that removed race as a predictor of coalition. “In just a few minutes—so you have a lifetime of experience, supposedly, of learning race—but people stopped categorizing by race in their memory systems and their implicit ways,” says Tooby.

Cosmides describes a series of experiments that were the first ever in psychology to demonstrate a female advantage in spatial cognition, which they accomplished by testing spatial abilities that would have benefitted a gatherer rather than a hunter in an early human environment. “It’s not because the scientists were male or female or anything like that. It’s because they were starting from a theory about the adaptive problems our ancestors faced,” states Cosmides.

The psychologists also discuss how their perspective differs dramatically from the traditional view of the mind as a blank slate that passively records and accepts what it’s exposed to. “In an evolutionary psychology model, the person is in a really strong sense inventing themselves, instead of just downloading the environment and becoming what you’re told to be,” says Tooby.

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Interview by Nick Gillespie. Edited by Justin Monticello. Shot by Paul Detrick, Alex Manning, and Zach Weissmueller. Music by Yusuke Tsutsumi.