Free will is the idea that we can influence the direction that our lives and those of others will take by the choices that we make. Whether we have free will or whether we live in a world in which our fate is predetermined is one of the unresolved questions of science and philosophy. What we believe to be the answer to this question has profound implications for our personal wellbeing and that of society. I will, therefore, begin this series of articles with a discussion of whether we have free will.
Causality and Determinism
Causality relies on objects and events occupying a region of space-time so that the beginning of one, the cause, precedes the beginning of another, the effect. The region of space-time occupied by the cause must also contain the beginning of the effect.
A deterministic universe is one in which everything, including events and physical objects, has a cause. This implies that everything can be traced back to one original cause, the big bang, and that everything which subsequently occurred, including our decisions, was predetermined at that time.
Acausality and Indeterminism
Not everything in the universe has a cause. Space, time, and the laws of the universe are thought to have originated with the big bang. Thus, the big bang cannot be said to have had a cause. Some other mechanism may have been in play but, although we do not know what, it was certainly not causality.
There are other events which appear to be acausal. The radioactive decay of atoms and the appearance of virtual particles seem to occur at random, without any apparent cause. It may be that these events do result from some, yet unidentified, mechanism, but if anything “beyond” space-time is involved then, in the same way as the big bang, this mechanism is acausal.
Some of these acausal events interact with existing particles creating very small changes. As time passes, these changes can propagate and become magnified to such an extent that circumstances after the interaction are fundamentally different to those which might have prevailed without it. Furthermore, there will be infinitely many consequences of acausal events propagating through the universe. If they are truly acausal, then the result will be a probabilistic and unpredictable universe.
There would be no simple rules from which the state of the universe could be derived. Rather, such rules would be at least as complex as the universe itself. This, in turn, implies either that there is some entity as complex as the universe capable of holding those rules or that the rules and the universe are one and the same thing. The latter is, of course, the simpler and more likely explanation.
So, the existence of acausal events would imply that the universe was not predetermined by the Big Bang but rather by the most recent acausal event of any significance.
Determinism suggests that, after the point in time called “now”, the state of the universe is already mapped out and may even pre-exist. Indeterminism, on the other hand, implies that the future is uncertain or probabilistic, and, as it becomes ever more remote, increasingly so. Thus, knowing the situation at any point in time, we could only predict the future with reasonable accuracy a very short time ahead.
We cannot visit the future to know whether determinism or indeterminism is correct. However, if the former, then we are following a path already mapped out and have no free will. On the other hand, if the future is probabilistic and only becomes certain as “now” progresses through time, then it is possible that we do have free will.
There is no proof one way or the other. However, a popular acceptance of determinism has implications for us as individuals and for society. These include a fatalist attitude and a belief that we are powerless in the face of humanity’s difficulties. They also include a denial of personal responsibility for our actions and the damage that this might cause to society.
In my next post, I will discuss the evidence in favour of free will and expand on the consequences of its denial.