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.

Science or philosophy

Pierre Teilhard de Chardin

In a previous post, speaking about intelligence, I mentioned that there are four incompatible philosophical theories that try to explain the phenomenon of human consciousness. I summarize them briefly here:

1.     Reductionist monism or biological functionalism: The mind is completely determined by the brain and by the network of neurons that makes it. The human mind is an epiphenomenon. Freedom of choice is an illusion. We are programmed machines.

2.     Emergent monism: The mind is an emergent evolutionary product with self-organization, which has emerged as a complex system from simpler systems made up by neurons. Some argue that the underlying structures cannot completely determine the evolution of the mental phenomena. These, however, would be able to influence the underlying structures.

3.     Neuro-physiologic dualism: Mind and brain are different, but they are so closely connected that they make up a unit, two complementary and unique states of the same organism.

4.     Metaphysical dualism: Mind and brain are two different realities. The first is spiritual and non-spatial, capable of interacting with the brain, which is a material and spatial substance. Both entities can exist independently of one another, although the body without the mind eventually decomposes.