Different types of chance

Jacques Monod

When we don’t know why something happens, we usually say that it is due to chance. But this statement is ambiguous, because there are two different types of chance:

• Epistemological chance, where the cause of what’s happening is well-known, but so complex that it remains outside the scope of our knowledge. Almost all games of chance (dice, roulette, lottery jackpot) are examples of this type of chance. Rolling dice conforms to the laws of mechanics, but the conditions are so complex that we cannot predict the result of each roll. This type of chance is what Jacques Monod called operational uncertainty in his book Chance and Necessity (1970):

This term is used... in relation to the game of dice, or roulette, and the calculation of probabilities is used to predict the result of a play. But these purely mechanical and macroscopic games are not "the result of chance" except because of the practical impossibility of controlling the throwing of the dice or the ball with sufficient precision. It is evident that a very high precision launching mechanism is conceivable, and would make it possible to largely eliminate the uncertainty of the result... The same thing happens, as will be easily seen, in... many phenomena where the notion of chance and the calculation of probabilities are applied for purely methodological reasons. (My translation into English).

The problem of Free-Will

In the current image of the world provided by physics, we have at one side, an apparent fuzzy determinism, because the universe is chaotic; at the other end we get indeterminism. What can we say about human freedom?

Free-Will, as envisioned by classical philosophers, is incompatible with determinism. But it would be a mistake to assume that it is the same as quantum indeterminism. When a radioactive atom disintegrates, it is not free; it is subject to the influx of probability. One atom may disintegrate ten times later than another, but its longevity has not been chosen individually, it is the result of the play of blind forces which, on the average, produce the effect that one half of the atoms must disintegrate in a perfectly defined time.

Determinism or indeterminism?

Modern science has revolutionized our vision of the world. In the eighteenth century, Newton's theory of gravitation could be considered established, and gave rise to a materialistic-deterministic vision of the universe which can be personified in one of the most significant scientists of the time, Pierre-Simon, Marquis de Laplace (1749-1827), whose fields of study covered mathematics, astronomy, chemistry and biology. The success of his studies on the dynamics of the solar system moved him to state that, if we knew the exact initial conditions of the universe, it would be possible to predict all its past and future development. This gave rise to materialistic determinism, so successful in the nineteenth century and still a part of the popular vision of the world, in spite of the three devastating attacks it has suffered during the twentieth century.

Chaos and catastrophes

Michael Crichton's novel Jurassic Park is an allegation against the unreasonable use of science. In the words of Dr. Ian Malcolm, one of the characters in the book:

Scientists are actually preoccupied with accomplishment. So they are focused on whether they can do something. They never stop to ask if they should do something. They conveniently define such considerations as pointless. If they don't do it, someone else will. Discovery, they believe, is inevitable. So they just try to do it first. That's the ga me in science. Even pure scientific discovery is an aggressive, penetrative act... Discovery is always a rape of the natural world. Always.

This problem arises especially in the scientific field that serves as the basis for Crichton's novel, genetic engineering, which poses many important ethical problems. There are many things that we can already do, or are close to achieving, but should they be done? I will mention a few:

The debacle of determinism

Isaac Newton

By the end of the eighteenth century, Isaac Newton’s theory of universal gravitation was well established. As this theory makes it possible to predict very accurately the orbits of the bodies in the solar system, the French astronomer Pierre Simon de Laplace believed he had sufficient reasons to say the following:

An intelligence that knew all the forces that animate nature, as well as the respective situation of the beings that make it... could cover in a single formula the movements of the largest bodies of the universe and those of the lighter atom. Nothing would be uncertain and both the future and the past would be present before his eyes.

This assertion became the dogma of deterministic materialism, a philosophical (not scientific) doctrine asserting that only matter exists (taking the term broadly) and that the whole history of the universe is determined. Therefore there is no human freedom, nor intentionality, nor final causes in nature. There are just efficient causes.

Laplace’s statement can be expressed in more modern terms:

If we knew the position and the momentum of all the particles of the universe at a given instant, we could predict all their past and future development.