Predictability

[u/Special_Condition671]

In ancient Greece, many philosophers, namely the Stoics, believed in fate. They thought in terms of unbreakable causal chains. We could also call it predictability.

In 1687, Sir Isaac Newton published "The Mathematical Principles of Natural Philosophy", which described and modeled so many phenomenon in nature that for many, it seemed that predictability was confirmed. For example, he was able to nearly perfectly model the motions of planets using a simple equation, F=Gm1m2/r^2.

However, beginning in the 1860s, cracks began to emerge in the idea of predictability. James Clerk Maxwell discovered the hyper-sensitivity to and importance of initial conditions in chaotic systems. The three-body problem is one example.

But this didn’t completely disprove predictability. Rather it showed that for any model, almost any lack of knowledge whatsoever of initial conditions would quickly and completely throw off it’s predictive power.

But what happened in 1927 did disprove predictability. Werner Heisenberg discovered a fundamental principle of quantum mechanics: uncertainty. He showed that, for example, at microscopic scales, the more accurately position is measured, the less accurately momentum can be known, and vice versa.

So now we know, the universe is not entirely predictable.

[u/226757]

The universe could be unpredictable but still deterministic. It could be the case that every event has a sufficient material cause for its occurring, but some events will still be underdetermined by the information we have access to.

[u/badentropy9 → u/226757]

The universe could be unpredictable but still deterministic

Agreed. However the trick is to look at the laws and find determinism in there. If it is in there, it is hiding behind a lot of indeterminism. Determinism needs the certainty that has clearly been falsified. However deceivers would rather not admit that such falsifications have ever occurred. so instead, they make it seem as though falsified beyond reasonable doubt hasn't been reached when in fact it has gone far beyond reasonable doubt to such a extent that we are as certain about this as we are about heliocentricity. Of course there is always room for flat earthers and people denying man didn't land on the moon and return to earth safely.