Which Alice?

Which Alice? Which Alice?

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Looking-Glass Logic "That's easy," replied Humpty Dumpty. "Take, for example, the statement that the Red King is asleep. Its opposite is that the Red King is awake. Clearly one of them is true and the other false. The Looking-Glass logician believes only the one which is false, hence he can't believe each of them separately. Yet the single statement that the Red King is both asleep and awake is a false statement, hence the Looking-Glass logician must believe this false statement. "And now that you have the key, the answers to my ten questions should all be obvious." Here are the answers that Humpty Dumpty gave to his ten questions: 1—Since the Looking-Glass logician believes the Red King is asleep, then the Red King must actually be awake. Therefore the Red King is not dreaming of Alice. (By dreaming, I don't mean daydreaming!) Since the King is not dreaming of Alice, then the Looking-Glass logician must believe that he is dreaming of Alice. 2—Since he (the Looking-Glass logician) believes that either the Red King or the Red Queen is asleep, then it is false that either the Red King or the Red Queen is asleep. This means that both of them are actually awake. Since the Red Queen is awake, then he must believe that she is asleep. (By the same token he must also believe that the Red King is asleep.) 3—He believes the Red King is asleep, which merely means that the Red King is awake. This tells us nothing about whether the Red Queen is asleep or not, so we have no way of knowing whether he believes she is asleep. 4—This is a different story! Since he believes that the Red King is asleep, then it is false that the Red King is asleep. Hence it is certainly false that the Red King and Queen are both asleep! Therefore he must believe that they are both asleep. So the curious thing is that he doesn't necessarily believe that the Red Queen is asleep, yet he does believe that the Red King and the Red Queen are both asleep! 5—He believes they are both asleep, from which only follows that at least one is awake. We don't know which one, hence we cannot determine whether or not the Looking-Glass logician believes the King is asleep. 6—Since he believes that they are either both asleep or both 125

Looking-Glass Logic<br />

"That's easy," replied Humpty Dumpty. "Take, for example, the<br />

statement that the Red King is asleep. Its opposite is that the Red<br />

King is awake. Clearly one of them is true and the other false. The<br />

Looking-Glass logician believes only the one which is false, hence he<br />

can't believe each of them separately. Yet the single statement that<br />

the Red King is both asleep and awake is a false statement, hence<br />

the Looking-Glass logician must believe this false statement.<br />

"And now that you have the key, the answers to my ten questions<br />

should all be obvious."<br />

Here are the answers that Humpty Dumpty gave to his ten<br />

questions:<br />

1—Since the Looking-Glass logician believes the Red King is<br />

asleep, then the Red King must actually be awake. Therefore the<br />

Red King is not dreaming of <strong>Alice</strong>. (By dreaming, I don't mean<br />

daydreaming!) Since the King is not dreaming of <strong>Alice</strong>, then the<br />

Looking-Glass logician must believe that he is dreaming of <strong>Alice</strong>.<br />

2—Since he (the Looking-Glass logician) believes that either the<br />

Red King or the Red Queen is asleep, then it is false that either the<br />

Red King or the Red Queen is asleep. This means that both of them<br />

are actually awake. Since the Red Queen is awake, then he must<br />

believe that she is asleep. (By the same token he must also believe<br />

that the Red King is asleep.)<br />

3—He believes the Red King is asleep, which merely means that<br />

the Red King is awake. This tells us nothing about whether the Red<br />

Queen is asleep or not, so we have no way of knowing whether he<br />

believes she is asleep.<br />

4—This is a different story! Since he believes that the Red King is<br />

asleep, then it is false that the Red King is asleep. Hence it is<br />

certainly false that the Red King and Queen are both asleep!<br />

Therefore he must believe that they are both asleep.<br />

So the curious thing is that he doesn't necessarily believe that the<br />

Red Queen is asleep, yet he does believe that the Red King and the<br />

Red Queen are both asleep!<br />

5—He believes they are both asleep, from which only follows that<br />

at least one is awake. We don't know which one, hence we cannot<br />

determine whether or not the Looking-Glass logician believes the<br />

King is asleep.<br />

6—Since he believes that they are either both asleep or both<br />

125

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