thought experiment

Originally posted by twhitehead
What you don't seem to understand is that behavior is dependent on inputs, so for a neurophysiologist to claim that he can predict your behavior he must also know all your inputs including the fact that he will tell you that he has predicted that you will raise your hand. If he is telling the truth and has actually got an accurate formula and does not wha ...[text shortened]... time is actually a fundamental law of science. In fact, time is a result of information flow.

The impossibility of passing information back in time is actually a fundamental law of science. In fact, time is a result of information flow. WHITEY

The thought experiment said nothing about time travel , only deterministic predictions. In theory everything should be predictable in your view apart from randomness , but are you really suggesting that conscious choosing to not raise your arm is random?

Originally posted by Pawnokeyhole
But to be true, libertarian free will requires both the determinism and haphazardism be false.

But an alternative is a little hard to understand, isn't it?

But to be true, libertarian free will requires both the determinism and haphazardism be false. NEME

No it only requires that determinism can be voluntarily defied in certain circumstances.

Originally posted by Pawnokeyhole
Isn't this also true in the human case? Isn't the failure to predict in the human case also due to the fact that one of the inputs, namely what information is given to the human person, doesn't feature in the initial computations?
Isn't this sufficient explanation for the failure to predict? Hence, doesn't the analogy entirely fail to bear on the truth of determinism?

Yes and I agree with you fully and my post was intended to reflect that and hopefully clarify why.

Originally posted by knightmeister
The thought experiment said nothing about time travel , only deterministic predictions.

Go back and read the posts carefully and you will see the flaw in your thought experiment.

In theory everything should be predictable in your view apart from randomness , but are you really suggesting that conscious choosing to not raise your arm is random?
No, not everything is predictable as I clearly stated in my posts. You cannot predict an outcome if you do not know the inputs. For example can you predict for me the outcome of this:
IF x>5 GOTO 3 ELSE GOTO 8
will the computer go to line 3 or line 8?
It is a completely deterministic statement. You have claimed that is should be predictable now predict it.
You are going to say "but I don't know what x is". Well x is an input and without it you cannot do the prediction.
Now what if I tell you that x is the line that the computer goes to?
Think about it.

Originally posted by knightmeister
I found this on the net. I know that copy and pasting too much is not really on but I rarely do it so I thought I would indulge myself....



" Try the following thought experiment. Our
brilliant neurophysiologists come up with an equation
that they claim will predict all of our behavior. The
equation is so good that it even incorporates o ...[text shortened]... imply by deciding not to raise it, couldn’t
I instantly make the probability equal to zero?"

knightmeister,

This is nonsense. Essentially your argument is:

1. The computer can predict your behaviour, even when knowing when you know the prediction.

2. But I can defy that prediction, therefore determinism is false.

But this is a rubbish conclusion. All you have done is shown that 2. disagrees with 1. In which case the computer cannot predict your behaviour when you know the prediction, or, you cannot defy the prediction. Personally, I find 2. to be begging, as Twitehead essentially said.

To continue with the thought experiment, if your response was always to do exactly the opposite of the prediction, then yes, the computer would not come to a prediction. It simply cannot. But your actions are still determined because you are determined to do exactly the opposite of the prediction.

Originally posted by Conrau K
knightmeister,

This is nonsense. Essentially your argument is:

1. The computer can predict your behaviour, even when knowing when you know the prediction.

2. But I can defy that prediction, therefore determinism is false.

But this is a rubbish conclusion. All you have done is shown that 2. disagrees with 1. In which case the computer cannot pre ...[text shortened]... ns are still determined because you are determined to do exactly the opposite of the prediction.

It simply cannot. But your actions are still determined because you are determined to do exactly the opposite of the prediction. CONRAU

What if one were to not always do the opposite of the prediction?

Originally posted by twhitehead
Go back and read the posts carefully and you will see the flaw in your thought experiment.

[b]In theory everything should be predictable in your view apart from randomness , but are you really suggesting that conscious choosing to not raise your arm is random?
No, not everything is predictable as I clearly stated in my posts. You cannot predict a ...[text shortened]... ction.
Now what if I tell you that x is the line that the computer goes to?
Think about it.[/b]

I think this is a good point. I'm probably going to end up conceding defeat on this one. What you are saying is that as soon as one shares the prediction with the person then that contaminates the input and changes the outcome anyway. In essence predictions are impossible because of variable inputs but the process is still deterministic. I kind of get this. I actaully thought the most interesting aspect of the experiment (which was not mine) was that it showed how there needs to be a certain amount of unawareness of our destiny (if we have one) for determinism to work.

Originally posted by knightmeister
What if one were to not always do the opposite of the prediction?

Look. You have given a premise, that the computer will predict your behaviour even when you know what the prediction is. Your argument for free will essentially involves you negating that premise by insisting that we can defy that prediction. It is not an argument.

Originally posted by Conrau K
Look. You have given a premise, that the computer will predict your behaviour even when you know what the prediction is. Your argument for free will essentially involves you negating that premise by insisting that we can defy that prediction. It is not an argument.

In other words it would be impossible to make the perfect prediction and share it with the subject ? Or would it be possible to make the perfect prediction if you didn't share it?

Originally posted by knightmeister
In other words it would be impossible to make the perfect prediction and share it with the subject ? Or would it be possible to make the perfect prediction if you didn't share it?

You might be able to make the prediction without telling the subject, but never if you did.


BTW, a similar idea using statistical analysis of humans is written about in the novel Foundation and it's series.

Originally posted by knightmeister
But to be true, libertarian free will requires both the determinism and haphazardism be false. NEME

No it only requires that determinism can be voluntarily defied in certain circumstances.

If (a) voluntary action entails non-haphazardism, and (b) defying determinism entails non-determinism--the former proposition being highly plausible and the latter true by definition--then you haven't really denied my assertion, have you?

Originally posted by twhitehead
Yes and I agree with you fully and my post was intended to reflect that and hopefully clarify why.

I agree we agree 🙂

Originally posted by knightmeister
In other words it would be impossible to make the perfect prediction and share it with the subject ? Or would it be possible to make the perfect prediction if you didn't share it?

Since we are talking about a completely deterministic system with no random inputs then it is essentially identical to a computer program.
Given a computer program that takes inputs and gives outputs in a deterministic way, you can predict the outputs for any given input.
If we use the output as the input then there are two possible cases:
1. For a given input the output is identical to the input.
2. For the given input the output is different from the input.
So in some cases you can predict the output but not in others depending on the program.
If you are the sort of person that does whatever he is told he is going to do then I can correctly predict you will raise your arm, tell you that you will raise your arm and you will raise your arm as predicted.
If however you are the sort of person who does the opposite of what I predict you will do then I can never tell you my prediction and be correct.
However, none of this in any way indicates whether or not you are deterministic in nature since it applies equally well to the computer program which we know for a fact is deterministic.

Originally posted by twhitehead
Since we are talking about a completely deterministic system with no random inputs then it is essentially identical to a computer program.
Given a computer program that takes inputs and gives outputs in a deterministic way, you can predict the outputs for any given input.
If we use the output as the input then there are two possible cases:
1. For a gi ...[text shortened]... since it applies equally well to the computer program which we know for a fact is deterministic.

If however you are the sort of person who does the opposite of what I predict you will do then I can never tell you my prediction and be correct.


....what if was the sort of person who could choose whenever I liked to defy your prediction but I could also go along with it if I wanted? The original thought experiment only asks whether we "could" decide to defy the prediction not that we always would.

Originally posted by Pawnokeyhole
If (a) voluntary action entails non-haphazardism, and (b) defying determinism entails non-determinism--the former proposition being highly plausible and the latter true by definition--then you haven't really denied my assertion, have you?

My concept of free will is that all actions are determined by something and have reasons attached to them but that we get to choose which deterministic influence we are under the control of. For example , once a person has given themselves over to christ via the Holy Spirit there life is essentially influenced and determined to a greater and lesser degree by his spirit. We become servants of christ. Free will in the christian sense is about who we are allowing ourselves to become servants of ,christ or the things of this world. Free will still involves determinism . it's just that there isn't only one determined track we can ride on.