WE ARE ALL DESIGNIST NOW:

Twist #5 - Quantum Mechanics and the Defeat of Determinism

Most materialists deny that free will exists, and for centuries this seemed well-grounded in the findings of physics. The laws of physics appeared to be "deterministic," in the sense that what happens at a later time is solely determined through the laws of physics by what happened at earlier times. This was of course a troubling point for Judaism and Christianity, both of which held free will as a central tenant.

However, a truly astonishing reversal came in the 1920s with the discover of quantum theory. Barr describes it as "the greatest and most profound revolution in the history of physics" (27). It transformed the whole structure of theoretical physics, and in the process swept away physical determinism.

In prior centuries, the core of physical science was prediction. That's how theories were tested and proved. But with quantum theory, the present state of a physical system would not, even in principle, be enough to predict everything about its future behavior. No longer could you simply argue from the deterministic character of physics that free will was impossible.

Of course, this doesn't prove that we have free will. Instead, as Barr notes, "quantum theory simply showed that the most powerful argument against free will was obsolete. In the words of the great mathematician and physicist Hermann Weyl, 'the old classical determinism...need not oppress us any longer'" (27).

Opening the door to free will was just one of the effects of quantum theory. In its traditional or "standard" interpretation, it also posits the existence of observers who lie, at least in part, outside of the description provided by physics. That's a controversial claim, and has been challenged by radical reinterpretations of quantum theory (such as the "many-worlds interpretation") or by changing quantum theory in some way.

But as Barr writes, "The argument against materialism based on quantum theory is a strong one, and has certainly not been refuted. The line of argument is rather subtle. It is also not well-known, even among practicing physicists. But, if it is correct, it would be the most important philosophical implication to come from any scientific discovery" (28).

The above represents just a sampling of the major discoveries in the great history of science and faith. Barr spends nearly 300 pages examining them in more depth. If you'd like to learn more, I highly recommend you pick up Modern Physics and Ancient Faith for the rest of the story.

Tweet   @brothersjudd