If I Could Choose Again

  • #1
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I have often posed this thought experiment in debates on the “free will” question, and rarely does anyone provide a coherent answer.

The thought experiment is this :
Firstly, imagine that you take a “free will decision” to do something (for example, you decide to have tea rather than coffee with your breakfast).

And now imagine that the entire universe could be “reset” to a few moments before that “free will” decision, such that the properties of absolutely everything in the universe (including your internal brain states, desires, intentions, wishes, wants etc) are identical to the way they were the first time.

And now you choose again.

Would your choice necessarily be the same as it was the first time?

If “yes”, then this is determinism pure and simple.

If “no”, then what logical or rational explanation (apart from random or stochastic behaviour) could you possibly give for choosing differently?
 

Answers and Replies

  • #2
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Even though I don't see how our will might be free (from what, everything?) this experiment seems flawed. If an experimenter sets your intentions, wishes and wants to some previous state, is he not setting your will? How can you then call it free? The second decision to have tea is set by the experimenter to match the previous one. Maybe this is your point.
 
  • #3
russ_watters
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I don't see that contradiction, but I also don't see a logical reason why making the same choice twice implies a lack of freewill. If the situations are exactly identical, then your logic in making the choice is identical, regardless of whether the choice is really free or not. So I don't see how this thought experiment shows anything at all.
 
  • #4
Rade
...And now you choose again. Would your choice necessarily be the same as it was the first time?...
I think no, not if you have true "free will" to "think or not to think". That is, the second time around you may, using your free will to think about what to drink, freely decide not to think about either tea or coffee and decide to take a glass of milk. Unless milk is allowed this second time around, then you are correct, all is determined. If milk allowed, then the "logical explanation" for choosing different action second time is called "free will", when you accept that the definition of "free will" = volitional action of mind "to think or not to think".
 
  • #6
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The problem is that if your brain and body does not control your will, then that assumes duality or metaphysical properties which are outside the physical, and thus not provable.

Another problem is also that everything, even the metaphysical, must be deterministic.
 
  • #7
I totally disagree with the idea of free will to a maximum level available since we always make decision dependent on some other issues that guide us to do so. We may not realised it but all our decision are dependent on other experience that we have faced before!
 
  • #8
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Even though I don't see how our will might be free (from what, everything?) this experiment seems flawed. If an experimenter sets your intentions, wishes and wants to some previous state, is he not setting your will? How can you then call it free? The second decision to have tea is set by the experimenter to match the previous one. Maybe this is your point.
In a way, yes it is my point. The "experimenter" here is not actually doing anything to cause you to decide one way or another, he is just a passive experimenter who is simply replaying the outworking of the universe, he is not interacting with or affecting that outworking in any way.

What is "flawed" imho is the idea that free will (of the libertarian kind) is a coherent notion - and this incoherency is what the thought experiment illustrates.
 
  • #9
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I don't see that contradiction, but I also don't see a logical reason why making the same choice twice implies a lack of freewill. If the situations are exactly identical, then your logic in making the choice is identical, regardless of whether the choice is really free or not. So I don't see how this thought experiment shows anything at all.
If your choice is necessarily the same the second time around, then this is (as I said) determinism pure and simple. (determinism in simple terms is the thesis that "same past = same future").

In what sense could you consider your will "free" in this case? Only in the compatiblist sense, certainly not in the metaphysical libertarian sense (the latter being incompatible with determinism).
 
  • #10
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I think no, not if you have true "free will" to "think or not to think". That is, the second time around you may, using your free will to think about what to drink, freely decide not to think about either tea or coffee and decide to take a glass of milk. Unless milk is allowed this second time around, then you are correct, all is determined. If milk allowed, then the "logical explanation" for choosing different action second time is called "free will", when you accept that the definition of "free will" = volitional action of mind "to think or not to think".
OK. If "milk is allowed" then it is allowed both times (this is the way the experiment is defined).

And can you then offer a rational or logical explanation as to why you would choose milk the second time and not the first (given that all the antecedent factors are identical in both cases)? What rational explanation can we give for choosing differently, apart from random behaviour?
 
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  • #11
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What rational explanation can we give for choosing differently, apart from random behaviour?
The spiritualist might explain this by pointing out that if the will is indeed free then it is unrewindable. Since your experiment resets my will, it obviously assumes that it is not free, so you are proving your hypothesis by postulating it. You may be able to reset the material universe, but not the spiritual mind.
 
  • #12
russ_watters
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If your choice is necessarily the same the second time around, then this is (as I said) determinism pure and simple. (determinism in simple terms is the thesis that "same past = same future").
You're defining determinism and the scenario in such a way as to make it the only possibility. You're essentially saying 'if the universe is deterministic, is the universe deterministic?' So like I said, the thought experiment doesn't say anything about anything.

Drop the word "necessarily" from the question and reconsider it....
 
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  • #13
russ_watters
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If your choice is necessarily the same the second time around, then this is (as I said) determinism pure and simple. (determinism in simple terms is the thesis that "same past = same future").
"same past=same future" doesn't say anything at all about whether or not you have freewill. Consider the difference between hard and soft determinism. Basically:

Hard determinism: You don't have a choice.
Soft determinism: You do have a choice, but you'll make the same choice.

http://en.wikipedia.org/wiki/Determinism

Also, you may want to consider whether your premise is even scientifically possible. It may not be reasonable to assume it is possible to have identical states.
 
  • #14
Rade
....And can you then offer a rational or logical explanation as to why you would choose milk the second time and not the first (given that all the antecedent factors are identical in both cases)? What rational explanation can we give for choosing differently, apart from random behavior?
Because humans are given no automatic means to decide such things, humans are constrained such that they must make "choices" about which specific "choice" of action they will take (eg. drink tea [T], coffee [C], milk [M], etc. the second time around) to reach an end state or goal--let us call it [E].

So, for the simple example under discussion, let [H] = a human, [E] = goal (happiness from drinking) and [T], [C], [M] possible sets of actions to obtain [E]. Thus we have three possible trajectories:
[H] --> [T] --> [E]
[H] --> [C] --> [E]
[H] --> [M] --> [E]

So, at time (t)=0 suppose action [H] --> [T] --> [E] is selected. Now, we move forward in time, then rewind back to (t)=0, must [H] select same action ? I say no, not if we realize that the goal of the section process at (t) = 0 never was to select [T], [C], or [M] in the first place--but it was to select [E].

In other words, whenever [H] has to make choice among many different actions to reach a goal, and by definition the trajectory of action is not unique, then what we have is the process of selection by a "Markovian Machine". So, while the reaching of a goal [E] by a Markovian Machine is "determined", (that is, [E] must be obtained), the way to obtain [E] must be "random" in that the specific trajectory to be taken at (t) = 0 is a type of trial and error selection process.
Thus I suggest that human selection of any action = dialectic union of determinism + random​

and this then is my rational and logical explanation of why any human might select milk the second time around--in short, because humans are Markovian Machines.
 
  • #15
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Hard determinism: You don't have a choice.
Soft determinism: You do have a choice, but you'll make the same choice.
The distinction (imho) doesn't make any sense. If you will necessarily make the same choice then that is equivalent to saying that you have no choice (your choice is determined by the antecedent states). In other words, since you cannot choose differently to the way you do choose, you have no choice about your choice.

Also, you may want to consider whether your premise is even scientifically possible. It may not be reasonable to assume it is possible to have identical states.
This is not a "scientific" experiment - it is a logical (thought) experiment. Why should it not be possible? Can you suggest any reasons why it should not be possible?
 
  • #16
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Drop the word "necessarily" from the question and reconsider it....
If the choice the second time around is not necessarily the same, then it follows that the choice could be different, in which case (if it is different) what is the rational explanation for it being different?

If no rational explanation can be given for the choice being different, then what is the difference between this and random behaviour?
 
  • #17
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The spiritualist might explain this by pointing out that if the will is indeed free then it is unrewindable.
Why should it be "unrewindable"? Why should it be impossible (in principle) to recreate the precise conditions that applied before? Apart from claiming by arbitrary fiat "it is impossible", I see no rational argument which leads to the conclusion that it is impossible.

Since your experiment resets my will, it obviously assumes that it is not free, so you are proving your hypothesis by postulating it.
It makes no such assumption. I do not believe that Robert Kane (a leading defender of metaphysical libertarianism) would have any problem accepting the thought experiment as it stands, without claiming that it assumes the will is not free.

You may be able to reset the material universe, but not the spiritual mind.
Once again - why not? What rational, logical or empirical reason could you give for the belief that the spiritual mind could not be "reset"?
 
  • #18
Q_Goest
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Hi moving finger.
Seems to me the thought experiment is better when viewed with respect to various assumptions.

1. Assume the mind is computational: Then there is no free will in the common sense of the word. Computationalism is by definition, completely deterministic.

2. Assume the mind operates on classical mechanics: Then free will is highly questionable. The only way around having anything like a non-deterministic outcome is to suggest that at the level of classical mechanics, quantum mechanical deviations from the averaging we otherwise use may affect something at the classical level in an indeterminate way. Note this also assumes QM is not deterministic.

3. Assume the mind operates on a quantum level: Then free will may be real, depending on your view of whether it may be a deterministic QM world or not. If you insist QM is deterministic, realize what non-local means here. It means your decision was made for you either in the future or at some location in space that is so far away, no signal could have reached you unless it traveled faster than light.

Personally, I don't think free will is all that interesting. It can't be explained any better than experiencing the color red. We have not theory for either.
 
  • #19
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Because humans are given no automatic means to decide such things, humans are constrained such that they must make "choices" about which specific "choice" of action they will take (eg. drink tea [T], coffee [C], milk [M], etc. the second time around) to reach an end state or goal--let us call it [E].
Constrained? Thus free will (the metaphysical libertarian sense ) does not exist?
Thus I suggest that human selection of any action = dialectic union of determinism + random
I have no problem with the notion that everything is either determined or random or some mixture of the two. What I do have a problem with is how such a union generates “free will” in the metaphysical libertarian sense.
and this then is my rational and logical explanation of why any human might select milk the second time around--in short, because humans are Markovian Machines.
Agreed. But a Markovian Machine does not necessarily have free will in the metaphysical libertarian sense.
 
  • #20
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Firstly, I'd say it depends on the person you are examining.

Take for example a coffee junkie Joe. If you rewinded the sitation
100 times, then the coffee junkie will take coffee 100 times with
great probability.
I say probability because there could be some random
thought "popping up into his mind" that gives him the idea to drink
tea instead of coffee.
As to how and why this random thought pops up, I don't know.
(back to this later)

In other words, the choice of the person will depend on his previous
experience and preferences ("I like coffee").
There could also be another person Peter who drinks both coffee and
and tea but decides randomly every morning.

In other words, Joe and Peter's decision will depend on their experience.
And the experiment has to be considered in the framework of probability
( Prob(Joe drinks coffee)=99%, Prob(Peter drinks coffee)=50%.

So one could criticize the experiment because the person already could
have some preference. One should choose a situation where
the person has no preference, for example there are two doors which lead
to a big hall. Which door will the person take if you repeat the situation
several times?

In my opinion it will not always be the same door if you repeat the experiment.
(Apart from the preference thing, I think your thought experiment is interesting).

------

Secondly, maybe we should make clear first, what you mean with determinism.
In my understanding, determinism is to be considered in the sense of Laplace's
demon. Here, you have a supercomputer with infinite processor power.
You just plug in the information of all the particles in the world (position, velocity)
and can calculate a simulation of the universe.

We know however, that according to quantum mechanics there is no certain (inherent?) position and velocity of a particle, thus it is not possible to run the "correct" simulation. In fact, there is then no such thing as a "correct" simulation. At least that's my opinion.

-------

As to why random thoughts pop up (see coffee junkie Joe):
I think that quantum mechanics delivers a good argument. It may be that some parts of the brain can be described quantum mechanically: You have a wavefunction which only allows predicting probabilites for particles.

If we transfer this to the left-right door problem, then in the moment you
decided to take the left door, some wavefunctions collapsed.

Of course, the question is if quantum mechanics really applies to a macroscopic object such as the brain. And one could also criticize on how quantum mechanics provides a free will:
Is a "will" still involved or is everything random? Do I have any control on my decisions if some random process is involved.

This leads to the question: How is a "free will" defined?

-------

This article here may be interesting for you:
http://plato.stanford.edu/entries/determinism-causal/
 
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  • #21
1,604
1
Hi Edgardo

Thanks for your comments.

Firstly, I'd say it depends on the person you are examining.

Take for example a coffee junkie Joe. If you rewinded the sitation
100 times, then the coffee junkie will take coffee 100 times with
great probability.
I say probability because there could be some random
thought "popping up into his mind" that gives him the idea to drink
tea instead of coffee.
As to how and why this random thought pops up, I don't know.
(back to this later)

In other words, the choice of the person will depend on his previous
experience and preferences ("I like coffee").
There could also be another person Peter who drinks both coffee and
and tea but decides randomly every morning.

In other words, Joe and Peter's decision will depend on their experience.
And the experiment has to be considered in the framework of probability
( Prob(Joe drinks coffee)=99%, Prob(Peter drinks coffee)=50%.

So one could criticize the experiment because the person already could
have some preference. One should choose a situation where
the person has no preference, for example there are two doors which lead
to a big hall. Which door will the person take if you repeat the situation
several times?

In my opinion it will not always be the same door if you repeat the experiment.
(Apart from the preference thing, I think your thought experiment is interesting).
Everything you have described above is compatible with a simple mixture of determinism and random behaviour. Where does free will enter the picture?

Secondly, maybe we should make clear first, what you mean with determinism.
In my understanding, determinism is to be considered in the sense of Laplace's
demon. Here, you have a supercomputer with infinite processor power.
You just plug in the information of all the particles in the world (position, velocity)
and can calculate a simulation of the universe.
To me, determinism simply means "same past = same future", or in other words there is one and only one future which is consistent with the past.

We know however, that according to quantum mechanics there is no certain (inherent?) position and velocity of a particle, thus it is not possible to run the "correct" simulation. In fact, there is then no such thing as a "correct" simulation. At least that's my opinion.

QM shows that the world is epistemically indeterminable, but it is is not safe to conclude from this that it is necessarily ontically indeterminate. There is a fundamental and important difference. The difference is (however) totally irrelevant to the question of (libertarian) free will.

As to why random thoughts pop up (see coffee junkie Joe):
I think that quantum mechanics delivers a good argument. It may be that some parts of the brain can be described quantum mechanically: You have a wavefunction which only allows predicting probabilites for particles.

If we transfer this to the left-right door problem, then in the moment you
decided to take the left door, some wavefunctions collapsed.

Of course, the question is if quantum mechanics really applies to a macroscopic object such as the brain. And one could also criticize on how quantum mechanics provides a free will:
Is a "will" still involved or is everything random? Do I have any control on my decisions if some random process is involved.

This leads to the question: How is a "free will" defined?

Once again, everything you describe is a mixture of determinism and randomness. I have no problem with that. The important question is what does either have to do with free will?

This article here may be interesting for you:
http://plato.stanford.edu/entries/determinism-causal/

Thanks, I've read it already. :smile:
 
  • #22
703
13
Yes, you are right. Indeed the quantum mechanics argument
does not tell us if there'a free will.
As I said, I'm not sure how to define "free will".
My previous thought, before you pointed this out, was:

Is the world deterministic => YES or NO.
(a) If YES, we have no free will, everything is governed for all times (in your thought experiment this would mean: same past => same future).
(b) If NO, then we have a free will.

The latter is of course wrong, an electron's behaviour is not deterministic
(same past => but not same future
same wavefunction => but not same position where electron can be found).
but it certainly does not have a free will.

I think the major questions in this discussion are
(with respect to the quantum mechanics argument):

1) Does determinism hold for the person choosing between coffee and tea?
(your original question)

2) If not deterministic, does the person have a "free will"
(or is the person just "an electron" who has a certain wavefunction)??

3) How is "free will" defined?
(reminds of Data from Star Trek; does Data have a free will, remember
he's a machine and I think we all agree that machines
have deterministic behaviour).

--------

I once had a discussion with a friend. It was also about free will,
and he didn't believe in a free will while I did.
He then asked me, whether an amoeba had a free will.
I said yes (intuitively I said yes, because I didn't think
that an amoeba's behaviour is deterministic due to quantum mechanics)
while he said of course no.
His argument was that the amoeba is so small that it just reacts, it's
comparable to a tiny robot whose reactions are programmed, in other
words, the amoeba's behaviour is deterministic.

Another thing he mentioned about whether human beings had a free will
was the following:
For us, the amoeba has no free will, at least if we
compare our behaviour with that of an amoeba.
Our system called "human being system" stands above the "amoeba system"
Then my friend said, that a human being can't possibly recognize
in his own system if it has a free will.
There may be some other beings much more intelligent than humans,
to whom we appear as objects with no free will.

Lastly he said, it doesn't bother him if he has no free will, in the end
we don't notice. I have to agree, we don't notice.
This of course doesn't mean we should stop discussing :smile:
 
  • #23
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Why should it be "unrewindable"? Why should it be impossible (in principle) to recreate the precise conditions that applied before? Apart from claiming by arbitrary fiat "it is impossible", I see no rational argument which leads to the conclusion that it is impossible.

[...]

What rational, logical or empirical reason could you give for the belief that the spiritual mind could not be "reset"?
Spiritual or not, free will implies that your mind is not controlled by something external to it. It is either controlled or free, it cannot be both. Setting someone's mind to a specific state is controlling it, it denies free will. A thought experiment that does this will necessarily conclude that free will does not exist; it's in the premise.
 
  • #24
1,604
1
(reminds of Data from Star Trek; does Data have a free will, remember he's a machine and I think we all agree that machines
have deterministic behaviour).
Necessarily? Why should this be the case?

Lastly he said, it doesn't bother him if he has no free will, in the end we don't notice. I have to agree, we don't notice.
This of course doesn't mean we should stop discussing :smile:
I completely agree. We feel that we have free will, and we act like we have free will. It does not follow from this that we do have free will. But does it change the way that we live our lives? Of course not.

What DOES matter is that (if we are to call ourselves true philosophers) we should be true to logicality and rationality, and we should accept that this feeling of free will is an illusion.
 
  • #25
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Spiritual or not, free will implies that your mind is not controlled by something external to it. It is either controlled or free, it cannot be both. Setting someone's mind to a specific state is controlling it, it denies free will. A thought experiment that does this will necessarily conclude that free will does not exist; it's in the premise.
If the thought experiment "sets someone's mind to a specific state", then it only sets it to a state that already existed, hence nothing new is being introduced.

All the thought experiment is doing is to replicate a state that already existed. If the replicated state "controls" your will, then it only does so because the original state also "controlled" your will!!!!!
 
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