Neurons and free will

In another post in this blog I have described the four theories used by philosophers to try and solve the problem of human mind: What is intelligence? What is consciousness? What is free will? Are we actually free, or are we determined, just like meat machines?

At the end of last year, Javier Pérez Castells published a book where he addresses some of these issues from a scientific and philosophical point of view. Its title (in Spanish) is the same as the title of this post. In particular, chapter 8 of the book describes some of the models with which various scientists and philosophers have tried to explain how we make decisions more complex than those studied by the experiments performed by Libet, Fried and Haynes, which don’t go much further that pressing a button or raising a hand. These models are called two-stage, because they try to explain our decisions assuming that they are made in two phases: the first, more or less random, in which the brain generates the available alternatives, followed by a second phase, when we actually make a decision, after weighing those alternatives.

The Turing test

Alan Turing

In 1950, in an article published in the Mind magazine, Alan Turing wrote this:

I believe that in about fifty years' time it will be possible to programme computers, with a storage capacity of about 10⁹, to make them play the imitation game so well that an average interrogator will not have more than 70 per cent. chance of mating the right identification after five minutes of questioning.

Why precisely 70 percent? Because studies conducted, where some persons tried to deceive about their sex another person who couldn’t see them, gave that result. In seventy percent of the cases, the persons who had to guess if they were being cheated found the correct answer. In other words, what Turing said was this:

If the machine were able to deceive human beings, posing as human, with the same ease with which a human being can deceive another, it should be considered intelligent.