Brain Blindness

A Blindness in the Brain:

There is a tremendously interesting series being written on "unknown unknowns" starting here. As of this writing only the first three parts are published.

The argument being advanced is that there are things we don't just "not know" that we don't know, but things we cannot know that we don't know. It starts with a few amusing stories, but turns on the question of whether a known neurological disorder is actually just a very obvious example of a general problem with our brains.

An anosognosic patient who is paralyzed simply does not know that he is paralyzed. If you put a pencil in front of them and ask them to pick up the pencil in front of their left hand they won’t do it. And you ask them why, and they’ll say, “Well, I’m tired,” or “I don’t need a pencil.”

So, not only do they not know that they are paralyzed, they cannot know it. And they cannot reason to it: their reason, far from guiding them correctly, is inventing plausible rationalizations that let them avoid recognizing the problem.

So much for the disorder. But what about more general life?

DAVID DUNNING: I became very interested in judgments about the self, simply because, well, people tend to say things, whether it be in everyday life or in the lab, that just couldn’t possibly be true. And I became fascinated with that. Not just that people said these positive things about themselves, but they really, really believed them. Which led to my observation: if you’re incompetent, you can’t know you’re incompetent.

ERROL MORRIS: Why not?

DAVID DUNNING: If you knew it, you’d say, “Wait a minute. The decision I just made does not make much sense. I had better go and get some independent advice.” But when you’re incompetent, the skills you need to produce a right answer are exactly the skills you need to recognize what a right answer is. In logical reasoning, in parenting, in management, problem solving, the skills you use to produce the right answer are exactly the same skills you use to evaluate the answer. And so we went on to see if this could possibly be true in many other areas. And to our astonishment, it was very, very true.

But in part two, the question arises: does the disease being used as a model for this investigation even exist? And how would we know?

It's an interesting question, but it is a known unknown; the true unknown unknowns are what they're after. And those are, of course, very difficult things to pin down. Even incompetence is not a very good candidate. It is true that the same standard I would use to decide how to weld two pieces of metal (say) is the standard I would use to evaluate whether I was a good welder. But I am still able to reason to my incompetence at welding from the fact that I find that I have no standard for judging how to weld two pieces of metal; or how to turn on an arc-welder; or how to be sure I wasn't about to burn off my foot. I can very quickly reason to knowledge that I am not competent to be operating the welder, and need further instruction.

Yet apparently this is often not true, and it is interesting to examine why.

It is also interesting to speculate about the general thesis, which is that brain states can disable reason (or retask it to mere rationalization). This touches on the matter that St. Augustine discusses in "On Free Choice of the Will," where he asserts that it is necessary to believe before you can begin to understand. The choice to believe something, or not, alters the brain state; and it is obvious enough that this may open some new roads, and close off others. What is interesting is the reinforcement of Augustine's argument: the idea that, having not made the choice to believe, the road is invisible to reason. Would it not be true that, having made the choice to believe, other roads are closed and hidden? Reason cannot grasp that they exist, because when pointed in that direction it will merely reply, "I do not need a pencil."

That is troubling as well as fascinating as a concept, because it is impossible to know which side of that canyon one is on. This, too, becomes a known unknown.