Jul 4, 2011
Related to: The Comedy of Behaviorism
Behaviorism's gotten a bad rap.
It's gone down in history as the school founded upon the idea that there's no such thing as mental phenomena or cognitive processing, and if there are we can't ever know anything about them, and if we can I don't want to know about it, and if you tell me I will put my fingers in my ears and whistle, and SHUT UP SHUT UP I CAN'T HEAR YOU.
Actually it was more subtle.
The movement did begin with a variation on that principle for historical reasons. John Watson began his work thirty years before the first computer. Information processing still looked like magic; most scientists didn't realize that reductionist accounts of information processing were even possible. Neurons were still "the thing that Spanish guy keeps talking about". Today we discuss the brain by analogy to computers; in Watson's day, they discussed the brain by analogy to their own most advanced technology, mechanical devices. Today we talk about looking for mental programs and subroutines; they sought its gears and levers instead. And just as today many philosophers dismiss consciousness as an epiphenomenon of information processing because computers don't seem to be conscious, so Watson dismissed all mental states as an epiphenomenon of mechanical processing because mechanical devices didn't have mental states.
As science advanced, and as it picked up glimpses of cognition from the Stroop effect and early priming experiments, behaviorism became more sophisticated. Maybe its pinnacle of subtlety came with B.F. Skinner's "radical behaviorism" movement, which accepted inner mental life (which Skinner called "mental behavior") and sought to explain it.
If Skinner was willing to acknowledge inner life, why do we still call his theory behaviorist? It's hard and not especially profitable to define "behaviorism", but if I had to try I'd say it is a methodology that doesn't consider mental phenomena useful as a fundamental level of explanation. So if we want to know why Wanda runs away from a wasp, saying "because her previous encounters wasps have been negatively reinforced" is more useful than "because she felt scared".
And if Wanda herself says "No, I ran away because I felt scared," we shouldn't be especially interested in her opinion: she has privileged access to a certain type of output of the process generating her behavior, but not to the process itself.
Imagine the better behaviorists, if you like, as playing a worldwide half-century long game of Rationalist Taboo, in which you're no longer allowed to use words like "want", "feel", "hope", or "decide". It's overwhelmingly tempting to fake-explain psychology using non-technical non-explanations like "Oh, she just acts that way because she has an overly emotional personality" and so the whole school just promised themselves to root out that way of thinking.
Although the witticism that behaviorism scrupulously avoids anthropomorphizing humans was intended as a jab at the theory, I think it touches on something pretty important. Just as normal anthropomorphism - "it only snows in winter because the snow prefers cold weather", acts as a curiosity-stopper and discourages technical explanation of the behavior, so using mental language to explain the human mind equally halts the discussion without further investigation.
This idea of Rationalist Taboo also explains B.F. Skinner's "mental behavior" loophole. When he discusses thoughts as mental behavior, he's not using them as explanations for other things - not taking the easy way out and saying "The reason I stayed in tonight is because, after thinking about it, I decided I didn't want to go to dinner". He's taking an extra burden upon himself, trying to come up with explanations for thoughts as well as actions.
Behaviorism became less popular in the 1950s after clever experimental protocols allowed more direct measurement of what happens inside the mind, making its taboo on mental occurrences unnecessary and restrictive. Although the philosophical commitments involved became obsolete, the scientific findings remain as valuable as ever. They have entered into the new paradigm as "reinforcement learning", a process widely believed to underlie many diverse mental subsystems all the way from motor coordination to social behavior.
Although reinforcement learning is almost universally known, Skinner's philosophical context for the process is not. He believed that the Darwinian evolution of organisms was just one instance of a wider principle called "selection by consequences", the most successful optimization process in the history of the universe. Evolution can successfully design permanent features of an organism like its skin, claws, and eyes. But it is too slow to fully optimize an organism's behavior, and too large-grained to produce complex behavior on its own. It is is especially too slow and large-grained to produce human-level behavior: citing my sources in MLA format is an important skill, and I don't want to have to wait until ten generations of my ancestors have perished for citing their sources incorrectly before I can do it right.
So evolution conjured up a mini-evolution to serve it. Reinforcement learning is evolution writ small; behaviors propagate or die out based on their consequences to reinforcement in a mind, just as mutations propagate or die out based on their consequences to reproduction in an organism. In the behaviorist model, our mind is not an agent, but a flourishing ecosystem of behaviors both physical and mental, all scrabbling for supremacy and mutating into more effective versions of themselves.
Just as evolving organisms are adaptation-executors and not fitness-maximizers, so minds are behavior-executors and not utility-maximizers. This returns us to the case of the blue-minimizing robot, which executed its program without any representation of a "goal". Behaviorism holds out the prospect of an explanation of human behavior based on similar lines.
Despite its subsumption by the cognitive paradigm, behaviorism continues to hold a special place because of its association with reinforcement learning, as well as its uses in industrial psychology, applied psychology, and various successful therapies including the famous CBT. It's also one of the major inspirations for connectionism, a more modern and exciting eliminativist model which we'll return to later.
This sequence will continue by exploring some of the basics of reinforcement learning in the behaviorist paradigm, and then get into more controversial applications of the theory to explain previously mysterious human behaviors.