# Is determinism logically flawed?

If determinism is true, every event shall have a cause.

So, what is the cause of the first event (which is the first cause)?

1) every event shall have a cause -> First event/cause shall have a cause

2) first event shall be first (prior to all other events/causes) -> first event/cause shall not have a cause

It is known that self-reference is basis for some logical problems/paradoxes (https://en.wikipedia.org/wiki/Self-reference).

This conflict is also based on self-reference -> how can (the beginning of) determinism be explained by determinism (every event shall have a cause)? Self-reference, because determinism is "referring to" itself (its beginning)

The question is: is this reasoning correct? Is determinism actually logically flawed?

• Your argument presupposes a first event. What justifies this presupposition? – Eliran Aug 4 '19 at 18:40
• Consider the integers ..., -4, -3, -2, -1, 0, 1, 2, 3, ... Each number has a direct predecessor yet there is no first element. If causality works that way, it would be perfectly consistent. Of course one could then ask, what cause the entire sequence to come into being? It's turtles all the way down. – user4894 Aug 4 '19 at 19:39
• "If determinism is true, every event shall have a cause." If by event you include initial events, then I disagree with that premise. If the universe were analogous to a computer program running on a Turing Machine, I would call it deterministic. There's no logical reason why the universe can't be this way, but if it were, your definition simply wouldn't apply if it had an initial state. I'd still want to call such a thing deterministic, which means the problem I have is more with your definition than the actual things you're finding conflict with. – H Walters Aug 4 '19 at 19:59
• i agree with @Eliran and why think the first cause is an "event"? – user38026 Aug 5 '19 at 3:11
• The problem with arguments like this one, the ontological argument for god or the Kalam cosmological argument, is that they apply common sense to situations where modern physics tells us for a fact that this common sense does not apply anymore. They might have had some traction up to the XIX century but relativity and quantum mechanics have since leveled the playground. – armand Jan 26 at 10:57

I'd say it is not so much logically-flawed as non-reductive or not fundamental, and for the reasons you give.

A fundamental theory cannot rest on a caused phenomenon or event. Hence an argument for Materialism is an ironic argument for a Divine Creator or miraculous origin.

For a solution one would have to examine the Perennial notion of a 'causeless cause'.

Modern determinism in the scientific sense is basically only about mathematical prediction--if the universe is deterministic that means complete knowledge of the universe's physical state at an earlier time can be used to predict the physical state at a later time with perfect accuracy, no additional notions associated with philosophical ideas about "causation" are included. Here is philosopher of science Timothy Maudlin talking about the subject:

As for causation, everyday causal locutions are highly context-sensitive and subject to pragmatic considerations. One does not want any foundational physical concepts to have these features, so at least everyday causal locutions cannot be translated cleanly into basic physical terms. Furthermore, physics gets on fine without mention of causation: dynamical law does all the work. So there is no need to admit some new irreducible notion of causation to make sense of physics. A deterministic physics might endorse a claim like “earlier global physical states cause later global physical states”, but that claim is of little use for everyday talk of causes.

Also note that because all the known fundamental laws of physics have the property of either time-symmetry or CPT-symmetry, it is equally possible to predict earlier states given complete knowledge of the universe's state at a later time, the various arrows of time we see (asymmetries between past and future) are thought by most physicists to all be due to the the universe being in a low-entropy state around the time of the Big Bang, for reasons that are not really understood (there's a good discussion of the arrow of time and its connection to low-entropy initial conditions in Brian Greene's book The Fabric of the Cosmos). So if the philosophical notion of "causality" includes the notion that past events cause future ones but not vice versa, there is really nothing corresponding to this idea in modern physics.

Yes and no.

As a theoretical idea, a simplified model of reality, determinism is quite logical, a practical shortcut to make classical physics easier to understand and predict.

Believing that determinism is an accurate description of reality is logically flawed, very much so.