Uncertainty About Free Will

Martin Heisenberg, son of the famous Werner, wrote a piece concerning the uncertainty of the existence of free will in Nature last month.

Our influence on the future is something we take for granted as much as breathing. We accept that what will be is not yet determined, and that we can steer the course of events in one direction or another. This idea of freedom, and the sense of responsibility it bestows, seems essential to day-to-day existence.

Yet it is under attack as never before. Some scientists and philosophers argue that recent findings in neuroscience — such as data published last year suggesting that our brain makes decisions up to seven seconds before we become aware of them — along with the philosophical principle that any action must be dependent on preceding causes, imply that our behaviour is never self-generated and that freedom is an illusion

Heisenberg is a neurobiologist at the University of Würzburg, where he studies brain function in Drosophila. He argues that in order to gain insight into free will, it is advantageous to study animal behaviour, such as the motor behaviour of E. coli.

As with a bacterium's locomotion, the activation of behavioural modules is based on the interplay between chance and lawfulness in the brain. Insufficiently equipped, insufficiently informed and short of time, animals have to find a module that is adaptive. Their brains, in a kind of random walk, continuously pre-activate, discard and reconfigure their options, and evaluate their possible short-term and long-term consequences.

So this suggests that decisions are not simply responses to external stimuli but they can be made internally, not only by humans but by all life, albeit randomly in many cases. The fact that a bacterium changes direction at all in the absence of external stimuli supports this view. Heisenberg argues that this is a rudimentary form of free will even if the bacterium is not conscious of itself and is not conscious of its random 'decision' to change direction.

Some define freedom as the ability to consciously decide how to act. I maintain that we need not be conscious of our decision-making to be free. What matters is that our actions are self-generated. Conscious awareness may help improve our behaviour, but it does not necessarily do so and is not essential. Why should an action become free from one moment to the next simply because we reflect upon it?

I like this idea.

To extrapolate, neurons in the brain must be firing randomly almost constantly in tandem with what you might call unrandom or controlled firing (just a hunch, I have no data to back that up). It seems possible that random firing of neurons in our brains might be the actual source of consciousness and free will. Throughout evolution, as brain size increased, more complex animals may have evolved consciousness, which allowed them to control and use these random firings to their advantage, e.g. the ability to make a decision which seems wrong in the short term but is actually beneficial in the long term. This decision making process, which goes against the immediate external stimuli, is what I would call free will. A decision based solely on external stimuli is simply what we call instinct. So free will is random in less complex organisms but is actually somewhat self-controlled in humans and some other species.

Robert Doyle has responded to Heisenberg in the latest edition of Nature and seems to agree.

The philosophers' standard argument against free will is simple and logical. If our actions are determined, we are not free. If nature is not determined, then indeterminism is true. Indeterminism implies that our actions are random. If our actions are random, we did not will them.

Heisenberg's proposal makes freedom a normal biological property of most living things, and not a metaphysical mystery or a gift from God to humanity. The genius of this proposal is that it combines randomness with an adequate macroscopic determinism consistent with microscopic quantum mechanics.

Interesting stuff.

Now, it's nice and sunny in Dublin and I think I'm in the mood for some ice-cream.

Or am I?