Free will or biological determinism?

SCTODAY

Neuroscience supports the existence of free will. This is demonstrated in Free Will, Causality, and Neuroscience, coedited by Bernard Feltz, professor emeritus at the UCLouvain Graduate Institute of Philosophy. Human beings can escape strict biological determinism.

The question of freedom, of the human being as a free being, is one of the most fundamental questions of philosophy’, Prof. Feltz says, when asked to place his work in the context of his philosophical research. Neuroscience brings its share of answers to the question of free will. It aims to account for human behaviour according to the brain’s structure and formidable complexity.

Contribution of neuroscience

To approach the problem of free will from this complexity,’ Prof. Feltz says, ‘it seemed to me worthwhile to focus on learning, which has a lot to do with memory.’

We owe our knowledge of short- and long-term memory to Eric Kandel, winner of the Nobel Prize in Medicine. Short-term memory is linked to a chemical change within the synaptic bouton (see box on ‘Information transmission’). The synapse is thus triggered more quickly. As it’s a simple chemical modification, the memory fades more or less rapidly. In the case of long-term memory, there is a synthesis of proteins which structurally modify the synapses in use. A series of outgrowths makes the synaptic bouton significantly more complex. This structure endures much longer. The memory therefore remains vivid as long as these modifications remain in place. Prof. Feltz likes to cite the example of a violinist to highlight the consequences of these discoveries. A right-handed violinist will hold the bow with the right hand but the left hand prances over the strings and does most of the work. It’s in the area of ​​the brain that controls the left hand that most of the learning will be stored. And this is verified experimentally: for some violinists, the volume of this area is five times greater than the average. ‘In other words’, Prof. Feltz says, ‘each individual’s brain is the reflection of its own history! Our brain’s material structure depends on childhood learning. And from the moment that behaviour has an impact on the brain’s biological structure, the linear character of causality – genes determine the brain which itself determines behaviour – is broken.

Stabilised neural circuits

Let’s address another learning mechanism, revealed by another Nobel laureate in medicine, Gerald Edelman, who developed the theory of neural group selection. For biologists, until 1950 it was simple: one gene, one character. The maxim is difficult to justify given we now know the rather limited number of our genes. Edelman's subsequently proven idea was that if the first phase of establishing the nervous system is achieved under strictly deterministic conditions, in the following phase hyperconnectivity develops between the sensory centres, the motor centres and the limbic system, which is the centre of emotion. This is like the formation of comprehensive maps. Any stimulation in a centre involves sending information to the other centres. Thus redundant connectivity appears, which opens up possibilities at the behavioural level. To understand learning mechanisms, it’s necessary to consider a second important element: a circuit that is used is thus stabilised. Take the example of learning to walk, which is achieved by imitation and by trial and error. Hyperconnectivity allows for many different learning strategies. The child makes a first attempt. The circuit which allows this test will be stabilised, particularly in connection with emotions. If the test is successful, it will be valued and the child will gladly resume the same position, which he or she will be able to refine so that, ultimately, the child can walk correctly. All the tests are memorised, by stabilisation of the neural circuits whose use has been tapped, and the link with emotions allows the child to use the most promising methods. ‘Real twins who have learned to walk thus no longer have the same brain’, Prof. Feltz explains. ‘The brain is an integral reflection of each person’s life. This is the concept of idiosyncrasy – “idio” in Greek is “specificity”. This ties in with Kandel. The brain carries traces of our entire history.

Being free

But what distinguishes the human is language. Edelman holds that learning language is like learning how to walk but with an important difference: certain nervous system structures are ‘on standby’ for language learning. The brain is not undifferentiated. At birth, the child is able to hear everything, learn any language. The child records everything. Then the child repeats words, builds sentences. The social environment determines the choices and the brain’s highly developed connectivity will be different from one language to another. So here we leave biological determinism behind and enter cultural determinism. ‘In addition’, Prof. Feltz says, ‘many philosophies of language emphasise the fact that language is the gateway to indeterminism. This is artistic creation. Language opens the way to that, to a behaviour that can be articulated and established over the long term.’ What characterises language? It’s the ability to invent, innovate, anticipate. Edelman conceives behaviour over a long time frame. The human being is able to foresee and organise his or her behaviour according to his or her goal, and is therefore free.

Being free,’ Prof. Feltz concludes, ‘is not being able to do anything. It’s being able to place one's behaviour into a system of personal meanings and to act according to this system over the long run. Hence free will exists. We’re not absolutely free – no one argues that – but we’re not subject to determinism either. Neuroscience suggests we’re free. Free will is perfectly feasible given the most recent discoveries in learning and neuroscience. This is good news philosophically.

Information transmission

The nervous system is made up of billions of networked cells called neurons. These are excitable cells that transmit and receive electrochemical signals. However, the transfer of information doesn’t take place via direct contact between neurons. In fact, the membranes of the communicating neurons don’t touch, separated by a small space called the synaptic cleft, synapses being the areas of interaction between two neurons. The synaptic bouton is the neuron’s most advanced, extreme part, just before the ‘empty’ space that constitutes the synapse. Since signals can’t pass through the synaptic cleft, transmission occurs through chemicals called neurotransmitters. They are generated by the neuron that sends the message and recognised by the one that receives it.

Henri Dupuis

A glance at Bernard Feltz's bio

It’s no exaggeration to claim that the relationship between the living and philosophy has always been a source of fascination for Bernard Feltz. When he was young, he first studied zoological sciences (graduating from UCLouvain in 1976) before turning immediately to philosophy (1980). He preferred the latter, carrying out a PhD at UCLouvain under the supervision of the great specialist in the philosophy of science, Professor Jean Ladrière. He defended a thesis on analytical and systemic approaches in biology. He then began his research career at the University of Namur in the Department of Science, Philosophy and Society. In 1992 he joined UCLouvain as a lecturer and in 2006 was appointed full professor at the Graduate Institute of Philosophy, which he also chaired from 2008 to 2011. His research has focused on science-society relationships, environmental philosophy and the philosophy of neuroscience.

.

 

Published on March 10, 2020