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
1,685
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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
1,685
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
705
15
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
1,685
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
1,685
1
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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  • #26
Rade
I continue to argue the position that the answer to the OP question is "no" because...

the goal of the section process at (t) = 0 never was to select [tea], or [coffee], or [milk] or [etc.]...the goal of the selection at (t) = 0 was to obtain [happiness] from drinking

And, it is easy to see how, if one puts equal value on drinking tea, or coffee, or milk to obtain happiness from drinking, then at any time (t) = 0 one can clearly use free will to select among different actions of equal value. Thus there is no good reason why, if time is reset, the person would not use free will to select some different action (say coffee) the second time if all options had equal value the first time at (t) = 0--seems to me that this is what it means to have "freedom of judgment".

Now, logically there are only two types of conditions that can effect any "selection" process (1) those external to the human mind and (2) those internal to the human mind. The OP thought experiment clearly resets both external and internal conditions, but one cannot "reset free will" otherwise it cannot be "free".

And, it does not hold that if the person the second time again does take tea that "all is determined"....

For example, it is possible to form a hypothetical situation that just before the first event at (t) = 0 the person said to itself, "you know, there is this person on PF who claims I have no free will , so here and now I freely decide that, to make myself happy, for next two drinks I will first take tea then coffee". So, if we reset to (t) = 0 again, the person will, for a second time, once again take tea using its free will decision (given the OP conditions that all else is also reset)--thus it is not always true that "taking tea a second time" must be example of "determinism" as presented by the conditions of the OP thought experiment provided.
 
  • #27
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Edgardo's friend is very close. If one takes the point of view (POV) an omniscient observer then everything is deterministic, but from man's POV we choose our choices. For example would you choose the right door or the left door?

Why?

If the decision is random then are not all decisions random? If choices are made from randomness then why not kill someone?

The same question can be posed to a purely deterministic theory. If I am made to kill someone with out choosing to then how can anyone judge me or punish me for the action I did not choose?

This is why freewill is important. With out freewill no one should be held accountable for anything. For a random theory, just because I killed this time doesn’t mean ill ever kill again, and everyone is just as likely to kill as me. For a deterministic theory, I was forced to do it by nature so there is no right for punishment and all our thoughts on justice and even morality are thrown out the window. (Morality because in a deterministic world the only moral thing to do is to do is what you have been determined to do.)

And just if you are wondering I get these thought from the Bible. It tends to say that both determinism and freewill are true.
 
  • #28
Rade
...As I said, I'm not sure how to define "free will"...
I also cannot find a definition for free will, thus I would say it is outside definition itself, it is a self-evident fact, known during any act of introspection--that is, one cannot focus on anything unless one is free to [focus or not focus]. Like existence and identity, free will is a philosophic axiom. To ask for a definition is to ask that a choice be made (to define it this way or that way), thus the "act of asking" for a definition of "free will" is itself to presuppose the reality of "free will".
 
  • #29
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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.

You're missing what actually matters. Free will is a quality of a free mind. A free mind cannot be set or reset at will by an external agent. If you can do this then the mind is not free. It does not matter if you set it to something it previously was or to something it previously was not. It is the fact that you can set it to anything at all that matters. Your experiment can only be performed on a controllable mind, it cannot be done on a free mind without explaining how you would control the state of a free mind in the first place. You need to resolve this contradiction before you start.


If the replicated state "controls" your will, then it only does so because the original state also "controlled" your will!!!!!

No, a state does not control a free will by definition of free. A replicated state does not do this either. It is the experiment(er) that controls the mind under study. Again, an experiment that sets something to a specific state controls it. Since you cannot control something that is free of your control, your experiment cannot be done on a free mind. If you perform it, it will be on a non-free subject therefore you must conclude that the subject is not free since it's the only truth that can come out of this.


PS: I am not arguing in favor of free will. I am just pointing at an experimental error. Free will is surely a misconception, but this experiment is not what proves it because it does not apply.
 
  • #30
Well this isn't so much a question of free will as it is opinion, and inherently taste. If you discover that coffee conflicts with an ulser to a greater extent than tea, on the day of the experiment, then you would probably choose tea every time. Though free will is still present.
Lets say that I just ate something that would not react well with coffee then yes, I would pick tea, though I would still be able to choose coffee if I felt as though that was what I wanted. Free will can be present though one option is much more appealing.
If you were able to turn back time then the same situations would have occured previous to the decision, so the same factors would be present and the same outcome. It is all dependant on previous factors, though if I felt incline I could choose to drink mud.
 

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