Logical Fatalism

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Logical Fatalism Logical Fatalism Before examining the problem of human freedom versus divine foreknowledge, it will be helpful to look at its predecessor: Logical Fatalism. Aristotle (in 350 BC) argued that, if we accept certain plausible assumptions about the nature of truth itself, then the future is already fixed. Let’s see how. 1. Truth Values of Propositions: A proposition is a meaningful statement. It ASSERTS something. For instance, the following are all propositions: <Richmond is in Virginia> <Unicorns exist> <There is a table in this room> <The Moon is made of cheese> Furthermore, all propositions have a truth-value: Namely, they are either TRUE, or they are FALSE. The first 2 propositions above are true, while the latter 2, sadly, are false. But, notice that the DENIAL of the two propositions on the right are TRUE: <It is not the case that I just saw a unicorn> TRUE <It is not the case that the moon is made of cheese> TRUE Thus, the following axiom of logic: The Law of Excluded Middle (LEM): Every proposition is either true, or its negation is. That is, necessarily, “Either P or not-P” is true. So, consider two people, who make the following claims: Fred says, <There is a table in this room> Wilma says, <There is NOT a table in this room> Without even looking at the room, we already know that ONE of these two people is right (i.e., is saying something true), and the other is wrong (saying something false). This is just the way truth works. 2. The Fixity of the Future: Now consider two people, who make the following claims about a future event. (Aristotle’s famous example is of a sea battle tomorrow.) Fred says, <Chad will buy coffee at The Daily Grind on Friday> Wilma says, <Chad will NOT buy coffee at The Daily Grind on Friday> 1 Who is right? They cannot BOTH be right. But, due to the Law of Excluded Middle, one of them MUST be right. That is, either Fred is saying something true, or else Wilma is. Aristotle writes, “if one man affirms that an event of a given character will take place and another denies it, it is plain that the statement of the one will correspond with reality and that of the other will not.” Put another way, “if one person says that something will be and another denies this same thing, it is clearly necessary for one of them to be saying what is true – if every affirmation is either true or false; for both will not be the case together under such circumstances.” Note that Aristotle is not saying that one of the two WILL be right. He is saying that one of them is PRESENTLY right. But, if that is the case, then the claim uttered by the person who is right must necessarily take place in the future! For instance, imagine that Fred is the one who is speaking the truth. In that case, Chad WILL buy coffee on Friday. What’s worse, there is no way that he can FAIL to buy coffee Friday. In short, due to the nature of truth, “nothing is or takes place fortuitously, either in the present or in the future, and there are no real alternatives; everything takes place of necessity and is fixed.” Then, “Everything that will be, therefore, happens necessarily.” Why Necessity? Imagine that you met Fred and Wilma back in 2010. They said to you: Fred says, <You will take Medieval Philosophy> Wilma says, <You will NOT take Medieval Philosophy> As they said it, one was speaking the truth, and one was speaking a falsehood. Sure, at the time, you didn’t KNOW which one of them was speaking the truth—but that doesn’t matter. Whether you knew it at the time or not, Fred was speaking the truth. Now, if Fred was speaking the truth, then it was ALREADY true in 2010 that you would take Medieval Philosophy. And this wasn’t just true in 2010. It was already true in 400 AD. It was even true a billion years ago! “But if it was always true to say that [an event] would be so, it could not be not so. … But if something cannot not happen, it is impossible for it not to happen; and if it is impossible for something not to happen, it is necessary for it to happen. … For a man may predict an event ten thousand years beforehand, and another may predict the reverse; that which was truly predicted at the moment in the past will of necessity take place.” 2 In other words, long before you were born there was already a FACT OF THE MATTER about whether you would take Medieval Philosophy. Namely, it’s been true all along that you WOULD take this class. But, then, it has always been impossible for you to NOT take this class. So, your decision to take this class has always been fixed, since forever. 3. The Argument: In argument form, the problem might look like this: 1. Necessarily, <Either you will buy coffee Friday, or you will not> is presently true (because the law of excluded middle is true). 2. Therefore, one of the following two propositions is presently true: (a) <You will buy coffee Friday> (b) <It is not the case that you will buy coffee Friday> (because a disjunction is true if and only if one of its disjuncts is true). 3. If (a) is true, then (a) is unavoidable (i.e., there is no way to make it false), and If (b) is true, then (b) is unavoidable. 4. Thus, either buying coffee Friday is unavoidable, or not buying coffee Friday is unavoidable. 5. This is generalizable to any proposition about the future; i.e., general fatalism about the future is true, such that your entire future is fixed and unavoidable. The result is that your entire future is already fixed and unavoidable. So, there is no free will. There is not even any random chance. There is one set future which is certain to happen, and no one has the ability to do otherwise. 4. Aristotle’s Solution: First, note that “either-or” statements are called disjunctions, and each half is called a “disjunct”. Perhaps you would agree that the following disjunction is presently true: <Either Chad will buy coffee Friday or Chad will NOT buy coffee Friday> TRUE Thus, you accept the Law of Excluded Middle. Nevertheless, you might be inclined to DENY that either of that statement’s DISJUNCTS is presently true: <Chad will buy coffee on Friday> Presently, neither true nor false <Chad will NOT buy coffee on Friday> Presently, neither true nor false Which one of these two will turn out to be the case is presently “up in the air”, so to speak. Therefore, at present, each of these two statements is neither true nor false. Sure, one of them will BECOME true on Friday (and the other will become false). But, until then, both statements lack a “truth value”. Aristotle writes, 3 It is necessary for there to be or not be a sea battle tomorrow; but is not necessary for a sea battle to take place tomorrow, nor for one not to take place – though it is necessary for one to take place or not to take place. … [I]t is necessary for one or the other of the contradictories to be true or false – not, however, this one or that one, but as chance has it; or for one to be true rather than the other, yet not already true or false. While it is necessarily the case that EITHER a sea battle will take place tomorrow, or it won’t, there is NOT presently a fact of the matter about which of these two possibilities will occur. In this way, Aristotle rejects fatalism and preserves the openness of the future. Problem: First, are all statements about the future really neither true nor false? [To see why this is odd, it may help to imagine that you and a friend are at a restaurant. You say, “The following is true: I am going to order a burger.” Later, you order a burger and say, “See? I was right?” But, your friend endorses Solution 1, and says, “Actually, you were wrong. For, at the time, your statement was neither true nor false—but, you mistakenly asserted that it was true.” How absurd!] Second, in order for a disjunction (e.g., “Either A or B”) to be true, one of its disjuncts must be true. That is, “Either A or B” is true iff either “A” is true, or “B” is true. [Imagine I say that “Either Anne or Brett was at the party.” Then you ask, “Was Anne there?” No, I reply. “Was Brett there?” No, I reply again. That’s impossible! The either-or statement can only be true if Anne WAS at the party, or if Brett WAS at the party (or both). It simply cannot be true if neither disjunct is true. The disjunction is only true when one (or both) of its DISJUNCTS is true.] Therefore, the only way that <Either Chad will buy coffee Friday or Chad will NOT buy coffee Friday> can be PRESENTLY true is if one of its disjuncts is PRESENTLY true. That is, one of the following two propositions must be PRESENTLY true: <Chad will buy coffee on Friday> <Chad will NOT buy coffee on Friday> Aristotle “solves” the problem of fatalism by denying this. He says, rather, that one of these statements will BECOME true on Friday.
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