Wednesday, February 23, 2011

Pigeons

That old curmudgeon H. L. Mencken wrote: "The most common of all follies is to believe passionately in the palpably not true. It is the chief occupation of mankind."

Admitting that no one -- including this writer -- is immune to self-delusion, still it is hard for anyone who respects empirical evidence to argue with Mencken.

Half of Americans believe in ghosts. Almost seventy percent believe in angels. More people believe in astrology than express interest in astronomy. Almost anything paranormal -- ESP, UFOs, channeling, etc. -- is deemed more interesting than science. Not to mention the eighty-three percent who believe in a God who hears and answers prayers.

Why so much belief in a total absence of non-anecdotal evidence?

Back in the 1940s, the behavioral psychologist B. F. Skinner did a famous experiment with pigeons that he thought had some relevance to human credulity. He put birds in the kind of cages used for training animals by reinforcement -- peck a bar, get some birdseed, that sort of thing. Except in this new experiment, the feed was provided at regular intervals regardless of what the pigeons did.

And guess what? The pigeons fell into certain behaviors all by themselves -- nodding or turning or pecking for food -- although their behaviors had nothing to do with the reward being offered. Skinner wrote: "A few accidental connections between a ritual and favorable consequences suffice to set up and maintain the behavior in spite of many unreinforced instances...The experiment might be said to demonstrate a sort of superstition. The bird behaves as if there were a causal relation between its behavior and the presentation of food, although such a relation is lacking."

"There are many analogies to human behavior," said Skinner. He was not the first to comment on the human propensity to mistake coincidence for causality.