Last time, I wrote about Reality Enhancement, that impulse by which we endow whatever we see with more being and intelligibility than it has on its own. And I argued that this is on the whole a good impulse: imagine standing in a dark room with only three glints of light as guide, with no ability to “reconstitute” the scene.
Now I want to describe RE’s first offspring, the Filter. The same impulse that leads us to seek clarity and intelligibility in the world leads us, when we have formed a theory of any kind, to look for whatever might fit with that theory. One form of this is the infamous “Confirmation Bias,” namely the tendency to notice things that fit with our theories and overlook things that don’t, to ask “What fits with my theory?” instead of asking “What doesn’t fit with my theory?” But the Filter has an even more subtle form: for each datum that goes by, we ask, “Does this fit my theory or not?”—and therein lies the trap. We notice when evidence fits or doesn’t fit the theory, but we don’t notice when the evidence would fit another theory just as well.
As a result, when a person holds a theory for a long time then he may see thousands and thousands of pieces of evidence that fit with his theory, and his confidence in his theory grows beyond all bounds, but he does not realize that all but a few of those evidences would fit another theory just as well. He says things like, “It’s hard to put into words, but after years of studying this subject I am just completely confident that this is true.”
Both the Filter and its more dangerous cousin, Confirmation Bias, can be in part overcome if we consciously promote the habit of asking whether the evidence in front of us could support a different idea. One can reach a point where the moment one thinks, “Here’s a theory,” the next moment one asks, “What other theory would the evidence support?” This is crucial for the intellectual life.
But in the end the Filter cannot be entirely overcome, because much of the time we are not aware that we have formed a theory or that we are testing it. The “theory” itself is often an intuitive reconstruction springing from Reality Enhancement, and the same impulse that caused us to clarify reality by connecting a few dots now causes us to be on the lookout for whatever fits with the resulting picture. The whole thing happens without our being aware of us, and we can no more get rid of it than we can train ourselves out of Reality Enhancement itself.
Which means that the Filter itself is not all bad. It is a natural extension of Reality Enhancement, which is on the whole a good thing. While RE actually changes our incoming perceptions, the Filter selects which perceptions or which aspects of those perceptions we will attend to, but both are born of the basic human impulse towards being and light. And who wants to destroy that?