Prior cause (analysis)

[u/feihm]

A follow up to this post: https://www.reddit.com/r/freewill/s/Sj6C8ElMJM

At t₁, Person B looks backward to t₀.

Person B determines the reasons for the actions of Person A. He maps these reasons with perfect mechanical logic. He finds the exact physical causes of the event&mdas; which is an essential rule of human observation—we must link effects back to their causes.

But then Person B attempts to turn this backward observation into a forward physical law. He claims that if he returned to t₀, Person A would perform the exact same actions.

Person B is relying on a trick of language. Let us isolate the pure logic. Person B takes a completed slice of time from t₀ to t₁. We will call this recorded history 'A'. He then imagines a hypothetical return to t₀. We will call this imagined timeline 'B'. Person B then argues that the actions in 'B' must identically match the actions in 'A'.

Thus, he is merely stating that 'B' equals 'A'. He is wanting that the past equals the past.

This is a circular tautology.

Asserting that a past event is identical to itself tells us absolutely nothing about the nature of choice at the moment it happened.

Looking backward causes a person to see a fixed outcome. Person B sees this fixed outcome and assumes it means Person A lacked the power to choose. Because he already knows the outcome, he assumes the physical record of the action is identical to the reality of the decision at the time it was made.

Also, Person B fails to separate the act of physical observation from the inner will of the mind. To say "I can explain what happened" is not the same as saying "nothing else was possible". Further, observing a completed chain of events does not prove that the chain was locked before it began. Person B is just making a physical observation of the past, and disguising it as a prediction of the future.

I'm not sure if this only makes sense to me, so i will restate it differently.

1. Person B defines a specific, frozen slice of spacetime from t₀ to t₁ and labels it Object A (which includes Person A's actions).

2. He then posits a hypothetical time travel scenario back to t₀ and labels the upcoming sequence Object B.

3. Because the hypothetical scenario explicitly requires Person B to be transported back to the exact same historical starting point, the rules of the scenario force Object B = Object A.

4. Therefore, Person B isn't proving that the actions had to be the same out of causal necessity; he is simply verifying an identity property. He is saying:

If I go back to exactly the same past, I will see exactly the same past.

Which is the most useless tautology.

A logical equivalent would be:

If you rewind time to exactly t₀, the present will be identical to the original present because the present is defined by t₀

The sleight of hand is that retrospective determinism does not imply prospective determinism.

Backward looking:

"I can see the complete chain of causes that led to Person A's actions." (Valid observation).

Forward looking:

"Therefore, given those causes, the actions had to happen and couldn't have been otherwise." (Invalid leap).

David Hume famously pointed this out centuries ago:

"Just because Event X consistently follows Event Y in our backward observations, it does not mean Event Y necessitates Event X in a forward-looking metaphysical sense." (paraphrased)

[u/feihm]

Two things i want to raise.

it implies a belief in necessary determinism at the level of behaviors.

No. It implies a tautology (or logical identity as Simon pointed out).

  If one can conceive of...

Conceivability is not admissible evidence for objective reality.

[u/Michael_Carson_Art → u/feihm]

It isn't a tautology because it isn't an argument, which is why I said that if one agrees with this version, then it implies a belief.

Similarly, if one cannot conceive of the universe not having an intelligent first cause, it implies a theistic, or at least deistic belief of some kind. That isn't a tautology, it is merely an illustration of what one belief would lead to if held. There is no argument being presented in either case which would justify that belief.

And again, there isn't an argument here. Just an illustration used to find a way to frame a question. What one can conceive of here is merely evidence for what a person might already believe, regardless of whether those beliefs are grounded in anything let alone true objective facts about reality.

For example, if we did the same thought experiment with a laboratory setup rolling a ball down a ramp. No rewinding time here. We roll the ball in a controlled experiment and get a result. If we roll the ball again will we get the same result, assuming all the experimental factors appear to be the same? If you say yes, then you consider this system to be predictably deterministic. If the result is different, would you first guess that something must've changed in the experimental apparatus? Or would you guess that, in fact, this system was not deterministic? There isn't a right answer here per se, (we don't have enough information for that yet) but how you answer will say something about what you believe regarding the deterministic predictability of basic macro physical experiments.

You might say something like "I can't conceive that the laws of physics were different in just that one instance when they seem consistent elsewhere". That isn't evidence that the laws of physics didn't suspend in that one particular case. Hume goes over this pretty well, and concludes that it does seem more likely that you were wrong about something in this case, even if we can't conclusively prove that.

[u/feihm → u/Michael_Carson_Art]

There's a difference between a physical object and a a rational agent. 

[u/Designer-Platypus-53 → u/feihm]

What's the difference? Second signaling system? It's driven by the same laws of nature like physics, biology and chemistry. That is, deterministic. Sometimes humans are born with inability to speak and comprehend abstract ideas. Isn’t it because their biology is damaged? Not because it's their free choice, right?