Diagram of the human brain

The last few posts describe only the dead ends that have been hit in AI. Other sciences searching for this same holy grail—a clear, evidence-backed model of human thinking—haven’t fared any better. Neurophysiology and Behavioral Psychology also keep striking out.

If a neurophysiologist could set up an MRI or similar imaging device and use his model of thinking to predict which networks of neurons in his brain would be active when he turned the device on and studied pictures of his own brain activities, in real time, then he and his colleagues could finally say they had formulated a reliable working model of what consciousness is. But on both the theoretical and practical sides, neuroscience is not even close to being so complete.

Patterns of neuron firings mapped on one occasion when a subject is performing even a very simple task unfortunately can’t be counted on. We find different patterns of firings every time we look. A human brain contains one hundred billion neurons, each one capable of connecting to as many as ten thousand others, and the patterns of firings in that brain are evolving all the time. Philosophers looking for a solid base for empiricism are disappointed if they go to Neurophysiology for that base.¹²

Similar problems beset Behavioral Psychology. Researchers can condition rats and predict what they will do in controlled experiments, but many exceptions have to be made to behaviorist explanations of what humans do in everyday life.

In a simple example, alcoholics who say they truly want to get sober for good can be given a drug that makes them violently, physically ill if they imbibe even very small amounts of alcohol, but that does not affect them as long as they do not drink alcohol. This would seem to be a behaviorist’s solution to alcoholism, one of society’s most intractable problems. But alas, it doesn’t work. Thousands of alcoholics have kept on with their self-destructive ways while on disulfiram.¹³ What is going on in these cases is obviously much more complex than Behaviorism’s best theories can account for. And this is but one simple example.

I, for one, am not disappointed to learn that the human animal turns out to be a very complex, evolving, open-ended piece of work, no matter the model under which we analyze it.