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The question of whether or not causal determinism (which I shall call simply determinism) is true may be unsolvable because of its inherent circularity. Let us suppose that a brilliant philosopher develops a very complex set of, say, 1000 symbolic propositions that prove the Universe is not deterministic. All those skilled in the trade look at the proof and agree: we now can say that the Universe is not deterministic with the same degree of confidence we say 1+1=2.
However, since the moment of the Big Bang it had been determined by natural law that as soon as any philosopher (or any other human being for that matter) achieved the proficiency required to make sense of that rigorous proof, the state of his brain would be such that he would be unable to detect a subtle flaw in one of the propositions, which made the conclusion untenable.
No philosopher would ever notice the error, because it would not be within the powers of his brain to see that there was an error in the first place. Of course, the debate between determinists and indeterminists would end, with a definitive victory of the latter.
Nonetheless, the Universe would still be, after all, deterministic! I know this story does not seem plausible (although I can recall a personal experience that is very similar), but one may say the same about causal determinism.
Does reality lead us to think determinism is true? No, it does not. On the contrary, in real life we often confront choice and decision, unpredictable events, incredible coincidences. In real life, all normal persons consider some actions unacceptable (undesirable / wrong) and other actions acceptable (desirable / right). Even the most primitive cultures reward some behaviors and punish others. Although the definitions of “good” and “bad” vary considerably for different people at different times, the concept of moral responsibility – and by implication, the idea that we have at least some degree of free will – seems to be universal. A modern philosopher expresses what is maybe a similar idea (van Inwagen, Peter. “The Mistery of Metaphysical Freedom” in Peter van Inwagen and Dean W.Zimmerman (eds.). Metaphysics: The Big Questions. Malden, MA: Blackwell. 1998. 365-74). On page 373 one reads: “And everyone really believes in metaphysical freedom, whether or not he would call it by that name. Dr. Johnson famously said, “Sir, we know our will is free, and there’s an end on’t.” Perhaps he was wrong, but he was saying something we all believe. Whether or not we are all, as the existentialists said, condemned to freedom, we are certainly all condemned to believe in freedom – and, in fact, condemned to believe that we know that we are free.”
For the sake of argument, assume that our world is in fact deterministic. Would it in any way invalidate the statements made in the previous paragraph? I am inclined to say that it would not. A determinist may add that natural law determines that human beings, individually and collectively, think and behave as if there existed such things as free will and moral responsibility.
However, it is then possible to say that determinism is of no consequence, and does not explain anything, since the only beings capable of formulating that concept (as far as we know) think and behave as if the concept was false
For the moment, let us just make this statement: “Human beings think and behave as if the world were not deterministic.”
There is no doubt that we see a lot of regularity and continuity in the world. Most of us would probably have a degree of confidence approaching certainty that the statements below are true or will turn out to be true:
- Coulomb’s Law is valid in Mars.
- One million years from now, Earth will still be turning around its axis.
- One thousand years from now salmons will be swimming and humming birds flying (provided, of course, the environmental impact of our species does not lead them to extinction).
The rationale for statements (a), (b) and (c) is the same: unchangeable laws of nature (which are deterministic) create part of what we perceive as reality. We expect that Coulomb’s Law will hold anywhere (case a); we expect gravitation to hold our solar system together for much longer than a mere 1,000,000 years (case b) and we expect that evolution keeps proceeding at its stately slow pace (case c). These laws are embedded in the structure of the present Universe and could not be otherwise. If they were otherwise we would not be here.
Other statements are of a different kind. There is some degree of confidence that they are or will turn out to be true, but not even close to certainty:
- Jones will be around for another ten years.
- Smith will not be killed by a criminal.
- Mary will win the Lottery next week.
The rationale for these statements is, in all cases, probabilistic. Jones believes he will be around for another ten years because that is what the actuarial tables tell him. He quit smoking many years ago, therefore he is more confident that this statement will become true (in this current state of the world) than he would be if he were still a smoker (another possible state of the world). Jones knows that if he eats more fruits and vegetables and exercises regularly, he can have even more confidence that statement (a) will become true.
The second statement is similar. In order to keep it general, let us say Smith is very worried about crime. He finds out the number of murders per 100,000 people in his home country, in the United States and in Japan: the figures are 29 – 4.7 – 0.3. Smith considers moving to Japan or to the US; it is not a trivial decision. He analyzes as thoroughly as he possibly can all aspects of the issue, makes a decision and acts accordingly.
The third statement is also similar but easily quantified. If Mary does not bet, the probability that she wins any money is zero; she may bet by choosing 6 out of 60 numbers and paying US$1. Mary may place any number of bets; each non-repeated combination of six numbers increases her odds of winning by 1 in 50,063,860.
Cases (a), (b) and (c) above are ordered in what I consider an increasing scale of randomness and a decreasing scale of susceptibility to the agent’s free will.
The outcome of these “experiments” is uncertain for Jones, Smith and Mary as individuals, but their actions take into consideration the obvious fact that there is some regularity in the world, mixed with some “noise”. The “noise” comes from the impossibility of accounting for all variables that affect deterministic laws plus the irreducible randomness of some phenomena.
No matter what the outcomes for Jones, Smith and Mary are, the actuarial tables will still be reflecting a true feature of the world, as will the crime statistics and the laws of combinatorial analysis.
Let us further suppose, just for the sake of argument, that James, Brown and Julia (who for all involved aspects and actions are equivalent to Jones, Smith and Mary) obtain different outcomes from these “experiments”. Say Jones lives twenty more years and James only five; both Smith and Brown move to Japan and Smith is eventually killed there; Mary wins the Lottery and Julia does not. Given the fact that all relevant variables were the same, do we have to ask “Why James and not Jones? Why Smith and not Brown? Why Mary and not Julia?” I would say that there is not much sense in asking these questions, since they are similar to asking why the experiment of rolling a fair die results in a 4 instead of a 5.
Probabilistic rules seem to account for other layer of causation that shapes our view of reality and this is the proper domain for free will. Most human actions unfold within this level of reality, because most of the time we are evaluating probabilities, even if we do not fully realize that we are doing so. Only at this layer a person can exercise that which, for all practical purposes, may be called “free will”, usually to increase the odds of achieving the best possible outcome according to his own judgment.
I am fully aware that all these examples can be “explained out” by determinism. However, what kind of explanation is that which can explain everything? By saying, “it happens because it had to happen”?
Finally, there are things that appear to be random. The prevailing interpretation of quantum mechanics suggests that there is some irreducible randomness at the foundations of the physical world. Doyle (“A Flaw in the Standard Argument Against Free Will?”. Web: http://gfp.typepad.com/the_garden_of_forking_pat/2009/06/a-flaw-in-the-standard-argument-against-free-will-1.html) suggests irreducible randomness manifests or has manifested itself in but a few points in the causal chain at the macroscopic level. I list only three of the points he mentions, because these appear to be almost indisputable
- at the original moment of the “Big Bang.”
- during genetic mutations, which eventually create new species, including “homo sapiens”.
- nine months before the birth of each us, when two sets of genetic information match to create a unique blueprint for a new human being.
I think that neither determinism nor indeterminism alone can provide an adequate explanation for what creates that “entity” we perceive as the real world. Maybe we could think about using a three-layered model:
- a deterministic layer of laws of physics, or natural laws;
- a probabilistic layer that human beings may change by using their free will;
- a truly random layer of causation that is the source of an infinite number of possible states of the wor