The Invisible Gorilla: And Other Ways Our Intuitions Deceive Us by Christopher Chabris and Daniel Simons is the latest attempt to popularize academic cognitive psychology – and probably the best book of its type.  The title comes from a cute experiment the authors constructed to show just how easily we miss glaring anomalies right in front of our eyes.  Try it; it’s fun.  But their point isn’t merely that people fail to notice the obvious, but that they falsely believe that they do notice the obvious.  Chabris and Simons call this “the illusion of attention”:

We experience far less of our visual world than we think we do.  If we were fully aware of the limits to attention, the illusion would vanish.

The authors actually commissioned their own survey of the public to back up this (and other) claims:

[M]ore than 75 percent of people agreed that they would notice such unexpected events, even when they were focused on something else.

Later chapters expose popular illusions about the accuracy of memory, overestimation of one’s own abilities, prediction, and – my personal favorite – human learning.  Chabris and Simons debunk the Mozart effect, then go after the New Age nostrum that “most people use only 10 percent of their brain capacity”:

This strange belief, a staple of advertisements, self-help books, and comedy routines, has been around so long that some psychologists have conducted historical investigations of its origins… There are so many problems with this belief that it’s hard to know where to begin… First, there is no known way to measure a person’s “brain capacity” or to determine how much of that capacity he or she uses.  Second, when brain tissue produces no activity whatsoever for an extended time, that means it is dead… Finally, there is no reason to suspect that evolution – or even an intelligent designer – would give us an organ that is 90 percent inefficient.

The authors go on to ridicule irrelevant brain scan rhetoric, myths about subliminal persuasion, and claims that you can improve your general mental ability with specific mental exercises.  Instead, they argue that recent experimental psych confirms the century-long literature on Transfer of Learning.  Contrary to popular belief and desperate teachers of irrelevant subjects, learning is highly specific.  The way to get good at X is to extensively practice doing X.

As an oblivious and forgetful man, I find most of The Invisible Gorilla completely plausible.  After I proof-read my writing on a computer screen, I often print it out and proof-read the hard copy, because I’ve found that merely changing the medium helps me notice overlooked errors.  And I’m so forgetful that I usually follow the rule, “If I want it done, I’d better do it now before I forget.”  My main objection to this book is philosophical.  Chabris and Simons end their book by lashing out at intuition.  But ultimately, as philosopher Michael Huemer argues, intuition (a.k.a. “common sense”) is all we have.  We don’t pit intuition against something else; we pit intuition against intuition.

Take the original invisible gorilla experiment.  It effectively undermines the intuition that almost everyone would notice a stray gorilla in a basketball game.  But the experiment wouldn’t be convincing without support from other intuitions, from “the video wasn’t doctored the second time around,” to “two eminent psychologists wouldn’t lie about their results,” to “my memories about the invisible gorilla experiment are reasonably accurate.”  The correct lesson to draw from the science isn’t that intuition is overrated, but simply that some plausible intuitions must be sacrificed to preserve other, even more plausible intuitions.