Brains and Computers

Computation and Consciousness

We have a perfect parallel between brains and computers. We can easily think of the brain as the hardware and mind or consciousness as the software or the operating system. We would be wrong, according to many philosophers, but I still think of it that way. Let me outline the compelling similarities (according to me) before getting into the philosophical difficulties involved.

A lot of what we know of the workings of the brain comes from lesion studies. We know, for instances, that features like color vision, face and object recognition, motion detection, language production and understanding are all controlled by specialized areas of the brain. We know this by studying people who have suffered localized brain damage. These functional features of the brain are remarkably similar to computer hardware units specialized in graphics, sound, video capture etc.

The similarity is even more striking when we consider that the brain can compensate for the damage to a specialized area by what looks like software simulation. For instance, the patient who lost the ability to detect motion (a condition normal people would have a hard time appreciating or identifying with) could still infer that an object was in motion by comparing successive snapshots of it in her mind. The patient with no ability to tell faces apart could, at times, deduce that the person walking toward him at a pre-arranged spot at the right time was probably his wife. Such instances give us the following attractive picture of the brain.
Brain → Computer hardware
Consciousness → Operating System
Mental functions → Programs
It looks like a logical and compelling picture to me.

This seductive picture, however, is far too simplistic at best; or utterly wrong at worst. The basic, philosophical problem with it is that the brain itself is a representation drawn on the canvas of consciousness and the mind (which are again cognitive constructs). This abysmal infinite regression is impossible to crawl out of. But even when we ignore this philosophical hurdle, and ask ourselves whether brains could be computers, we have big problems. What exactly are we asking? Could our brains be computer hardware and minds be software running on them? Before asking such questions, we have to ask parallel questions: Could computers have consciousness and intelligence? Could they have minds? If they had minds, how would we know?

Even more fundamentally, how do you know whether other people have minds? This is the so-called Problem of Other Minds, which we will discuss in the next post before proceeding to consider computing and consciousness.

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