the paradox of free will
yorker
Phil2-Lecture6-Short.pdf
Philo 2: Puzzles and Paradoxes
Free Will and Fatalism
The Paradox of Free Will
(1) Existence of Free Will: Agents sometimes act and choose freely. (2) Causal Determinism: Every event is causally determined to occur by some other events. (3) Incompatibilism: (1) and (2) are incompatible.
(1), (2), and (3) can’t all be true.
Reasons to Believe in Free Will…
In Favor of Free Will • (i) Feeling or experience of freedom. • (ii) We treat each other as if we were free.
• We hold each other morally responsible for our actions. And we generally do not hold people responsible when they are not in control of their actions or those actions were not chosen freely.
• Free will seems to be a condition on deserving credit for one's accomplishments.
• Free will seems to be a condition on the value we accord to love and friendship.
• (iii) In deciding what to do, we must treat ourselves as free.
Reasons to Believe in Causal Determinism…
Causal Determinism • Causal determinism is the view that the state of the world
at a given time (together with the laws of nature) wholly determines the state of the world at the next moment.
• Every event that occurs, including human action, is entirely the result of earlier causes and natural laws.
• The state of the universe, plus the laws of nature, determine a single unique future.
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Science and Determinism • Macro-level scientific theories seem to imply that macro-
level events follow deterministic laws. In particular, the laws of neurobiology and psychology seem to be broadly deterministic. So thought of it in this way, our choices seem to be determined by prior events in accordance with these laws.
• On the micro-level (the sub-atomic level), quantum mechanics tells us that the laws are non-deterministic or probabilistic. But this doesn’t seem to be much help in the present context. For being told that are choices the products of probabilistic laws is a kin to being told that they are random (within certain bounds). And randomness also seems incompatible with free will.
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“We may regard the present state of the universe as the effect of its past and the cause of its future. An intellect which at a certain moment would know all forces that set nature in motion, and all positions of all items of which nature is composed, if this intellect were also vast enough to submit these data to analysis, it would embrace in a single formula the movements of the greatest bodies of the universe and those of the tiniest atom; for such an intellect nothing would be uncertain and the future just like the past would be present before its eyes.”
- Pierre Simon Laplace, A Philosophical Essay on Probabilities
Laplace’s Demon
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IBM’s Demon?
Reasons to Believe in Incompatibility…
• “To say that one has free will is to say that when one decides among forks in the road of time (or, more prosaically, when one decides what to do), one is at least sometimes able to take more than one of the forks…One has free will if sometimes more than one of the forks in the road of time is ‘open’ to one.” (Peter van Inwagen)
• “One lacks free will if on every occasion on which one must make a decision only one of the forks before one -- of course it will be the fork one in fact takes -- is open to one.” (Peter van Inwagen)
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“… a deterministic view of human conduct … is inconsistent with the underlying precepts of our criminal justice system. A ‘universal and persistent’ foundation stone in our system of law, and particularly in our approach to punishment, sentencing, and incarceration, is the ‘belief in freedom of the human will and a consequent ability and duty of the normal individual to choose between good and evil’.”
- United States v. Grayson, 1978
An Argument in Favor of Incompatibility
• (1) If determinism is true, then every human action is causally necessitated by prior events.
• (2) If every action is causally necessitated, no one could have acted or chosen otherwise.
• (3) One only has free will if one could have acted or chosen otherwise.
• (4) Therefore, Casual Determinism is incompatible with the Existence of Free Will.
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Free Action and the Ability to Do Otherwise?
Three Options • Hard Determinism: Accept (2) and (3),
reject (1). There is no free will.
• Libertarianism: Accept (1) and (3), reject (2). Some human actions or choices are not causally determined.
• Compatibilism: Accept (1) and (2), reject (3). Reject the argument just given for Incompatibility.
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End of Part 1
How to Reject Incompatibility • Two basic ways of rejecting the argument for
incompatibility:
• (1) Reject the claim that one is only free if one could have acted otherwise.
• (2) Reject the claim that if every action is causally necessitated, then no one could have acted otherwise.
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One way to be reject Incompatibility, and defend Compatibilism, is to insist that a variety of options need not be metaphysically open to us in order for our will be free. Thus, free will is compatible with the inability to do otherwise.
Think again about the time traveler in the past on Lewis’s view. All things considered, she can’t change the past, but she can interact with the past - and she seems to be morally responsible for what she does in the past. So perhaps the sort of freedom of the will that matters does not require the ability to do or choose otherwise?
Compatibilism (1)
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Against “Able to Do Otherwise”
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But Lewis’s discussion of time travel also suggests a second possibility. Perhaps the sense of “able to do otherwise” that freedom of the will requires is different from the sense of “able to do otherwise” that is incompatible with causal determinism. Remember Lewis’s view on time travel. He writes that the although the time traveler can’t kill her grandfather all things considered, there is another sense in which she can do things other than what happened in the past. And this second, weaker sense of “able to do otherwise” is compatible with determinism. So perhaps all that freedom of the will requires is this weaker sense of “able to do otherwise”?
Compatibilism (2)
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In order for my choices and actions to be free in the sense relevant here, they must express or give voice to my character, my values, my desires, etc.
But this is possible, even when my character, desires, values, etc are themselves determined by outside forces and influences.
So Determinism and Freedom of the Will (in the important sense) are compatible.
The Compatibilist Thought
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But do either of these moves really remove the paradox? If my choices and actions are ultimately just the product of my genetics and my environment, can I really be said to be morally responsible for my actions?
After all, aren’t both my neurobiology and my upbringing ultimately just a matter of luck? So how can I be held responsible for things that are determined by these lucky or unlucky factors? For example, if this is true, do I really deserve to be punished for these actions?
Incompatibilism
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The Threat of “Moral Luck” “What we do is also limited by the opportunities and choices with which we are faced, and these are largely determined by factors beyond our control.” “Someone who was an officer in a concentration camp might have led a quiet and harmless life if the Nazis had never come to power in Germany. And someone who led a quiet and harmless life in Argentina might have become an officer in a concentration camp if he had not left Germany for business reasons in 1930.”
- Thomas Nagel, “Moral Luck”
Question #1
Do you think that Free Will and Causal Determinism are Incompatible?
A. Yes, and I believe we have free will, so Causal Determinism is false. B. Yes, and I believe in Causal Determinism, so we lack free will. C. No, because I don’t believe that free will requires the ability to do otherwise. D. No, because I don’t believe that Causal Determinism rules out the ability to do otherwise in the relevant sense.
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Question #2
Do you think that we are morally responsible for our actions even if we do not have free will?
A. Yes. B. No, but fortunately we do have free will. C. No, and we do not have free will, so none of us is morally responsible for our actions.
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Question #3
Compare a drunk driver who makes it home safely, purely as a matter of luck, with one who seriously injures someone in an accident. Do you think these two drivers are equally morally blameworthy?
A. Yes. B. No.
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End of Part 2
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The Problem of Fatalism
Causal Determinism vs. Fatalism
• Causal determinism is the view that every event that occurs, including human action, is entirely determined by earlier causes (plus laws).
• Fatalism is the view that whatever happens now and will happen in the future happens necessarily. • For the fatalist, because the present and future is fixed,
or pre-ordained, our choices about what to do in a situation seem inconsequential.
• Note: Fatalism leaves it open whether there is any purpose guiding our fates.
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As described by Taylor, fatalism is more than just a view about the future, it is also an attitude towards the future that is grounded in a view about the future.
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Fatalism vs. Free Will 1. Necessarily I will choose to eat a salad for lunch after
class. (Fatalism) 2. If necessarily I will choose to eat a salad for lunch after
class, then I could not have chosen to do anything else.
3. Therefore, I could not have chosen to do anything else.
4. My will is free with respect to an action, only if I could have chosen to do something else.
C. Therefore, my will was not free with respect to eating a salad after class.
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Arguments for Fatalism
• Thus, like Causal Determinism, Fatalism has seemed to many to undermine the existence of free will.
• Let’s look at two arguments for fatalism:
• Argument from Foreknowledge
• Aristotle‘s Sea Battle Argument
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Story of Osmo
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Richard Taylor, “Fate,“ pp. 58-60
Osmo reads the book, and finds, to his astonishment, a record of his life.
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Argument from Foreknowledge
1) Necessarily, if God (or anyone else) knows you will do x tomorrow, then you will do x tomorrow.
2) Necessarily, God knows that you will do x tomorrow. C) Therefore, it is necessary that you do x tomorrow. • The argument is valid. But is it sound?
• Note that this argument (unlike the argument from Determinism), does not rely on a scientific conception of reality.
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Contra Argument from Foreknowledge
• God’s omniscience does not require us to accept premise (2), that necessarily God knows you will do x tomorrow.
• When premise (2) is rephrased as follows:
then the argument from foreknowledge becomes invalid.
But isn’t God’s omniscience a necessary attribute of God? And doesn’t that imply that necessarily Gods knows what I will do before I choose to do it? Does this rule out free will?
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2*) God knows that you will do x tomorrow
• It all depends on why the author of the book of my life (e.g. God) knows what he knows.
• If the reason the author knows what I will do is because he controls my mind, then perhaps my will is not free.
• But if the reason the author knows what I will do is because he is a time traveller from the future who closely observed me and wrote everything down then my will might still be free.
• Question: can we think of God’s foreknowledge as being more like that of the time traveller?
• Video about argument from foreknowledge: https:// www.youtube.com/watch?v=iSfXdNIolQA
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Arguments for Fatalism
• Argument from Foreknowledge
• Aristotle‘s Sea Battle Argument
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Aristotle (384-322 BC) was a Greek philosopher and scientist born in Stagira. Aristotle was a student of Plato and the teacher of Alexander the Great.
The Sea Battle Argument can be found in Ch. 9 of Aristotle‘s work On Interpretation.
It is called the Sea Battle Argument because the future event of a sea battle was used as the example in it.
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Stagira
Aristotle‘s Sea Battle Argument
• Consider the fact that whatever is in future will, in the future, be in the past.
• And consider the idea that the past is fixed, that what happened in the past is necessary in some sense.
• Then the fact that a future event will be in the past implies that that event will be necessary in this sense.
• And if something will be necessary, isn’t it necessary now? How could something become necessary?
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An Aristotelian Argument for Fatalism:
1) Either it is true that E will happen, or it is true that E will not happen. 2) If it is true that E will happen, then E will be in the past. 3) If E will be the past, then E will be necessary. 4) Therefore, it is true that E will happen, then E will be necessary. (2,3) 5) If E will be necessary, then E is necessary now. 6) Therefore, if it is true that E will happen, then E is necessary now. (4,5) 7) And, by the same reasoning, if it is true that E will not happen, then E not happening is necessary now. C) Therefore, either E happening is necessary now or E not happening is necessary now. (1, 6, 7)
Aristotle‘s Solution • Aristotle argues that “future contingents” are neither true nor
false. In many cases, there isn’t a fact of the matter about what will happen in the future!
– Future contingents are contingent statements about future events that are neither impossible nor inevitable.
– E.g. “There will be a sea-battle tomorrow.”
– Thus Aristotle rejects the principle of bivalence or “law of excluded middle” in these cases: He rejects the claim that every declarative statement has exactly one truth value, either true or false.
• By rejecting that future contingents have truth values, Aristotle rejects premise (1) of the Argument. The “metaphysical openness” of the future.
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Aristotle and McTaggart
• Aristotle‘s idea that future contingents have no truth values makes sense if we adopt McTaggart‘s A-series of time. • According to the A-series, the passage of time brings
about changes in the truth values of a tensed statement. Aristotle could add, that the passage of time can give a truth value to a statement that did not have a truth value in the past.
• But B-series properties are timeless and permanent. • A sentence whose only temporal expressions are B-series
expressions is true at all times if it is true at any time. Given the B-series, it is not possible that there be fixed truths about the past and present, but not about the future.
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