A man of the State of Chêng was one day gathering fuel, when he came across a startled deer, which he pursued and killed. Fearing lest any one should see him, he hastily concealed the carcass in a ditch and covered it with plantain leaves, rejoicing excessively at his good fortune. By and by, he forgot the place where he had put it, and, thinking he must have been dreaming, he set off towards home, humming over the affair on his way.

Meanwhile, a man who had overheard his words, acted upon them, and went and got the deer. The latter, when he reached his house, told his wife, saying, ‘A woodman dreamt he had got a deer, but he did not know where it was. Now I have got the deer; so his dream was a reality.’ ‘It is you,’ replied his wife, ‘who have been dreaming you saw a woodman. Did he get the deer? and is there really such a person? It is you who have got the deer: how, then, can his dream be a reality?’ ‘It is true,’ assented the husband, ‘that I have got the deer. It is therefore of little importance whether the woodman dreamt the deer or I dreamt the woodman.’

Now when the woodman reached his home, he became much annoyed at the loss of the deer; and in the night he actually dreamt where the deer then was, and who had got it. So next morning he proceeded to the place indicated in his dream, — and there it was. He then took legal steps to recover possession; and when the case came on, the magistrate delivered the following judgment:– ‘The plaintiff began with a real deer and an alleged dream. He now comes forward with a real dream and an alleged deer. The defendant really got the deer which plaintiff said he dreamt, and is now trying to keep it; while, according to his wife, both the woodman and the deer are but the figments of a dream, so that no one got the deer at all. However, here is a deer, which you had better divide between you.’

— Herbert Allen Giles, A History of Chinese Literature, 1927

A dentist spotted a deadbeat patient while dining at his country club one evening. He called the patient aside, reminded him that he owed him $250 for work done more than two years earlier, and insisted the man pay up. To the dentist’s astonishment, the patient pulled a checkbook from his pocket and wrote a check to the dentist for the full amount.

Skeptical about the patient’s good faith, the dentist went directly to the bank the next morning and presented the check for payment. The teller handed it back with the explanation that the patient’s account was a little short of the amount of the check. Following a few minutes of good-natured conversation the dentist learned that the man’s account was twenty-five dollars short of the needed amount. The dentist smiled, went to the customers’ desk for a few minutes, came back to the teller, deposited thirty dollars to the account of the patient, and then again presented the check for $250 and walked out with a net gain of $220.

— Ralph L. Woods, How to Torture Your Mind, 1969

The audience at … a play are spectators of a world they are not in. They see what they may well describe as, say, Othello in front of a certain palace in Venice … [b]ut they are not themselves at any specifiable distance from that palace. …

I see Othello strangle Desdemona; but that will not entail that I, as part of my biography, have ever seen anyone strangle anyone. Nor need the actress who plays Emilia ever see a dead body; but Emilia does, for she sees the dead body of Desdemona.

“[W]e can in fact even visualise the unseen, because the fact that in visualisation I am as it were seeing is not itself necessarily an element of what is visualised.”

— Bernard Williams, Problems of the Self, 1973

If Socrates was born, Socrates became either when Socrates existed not or when Socrates already existed; but if he shall be said to have become when he already existed, he will have become twice; and if when he did not exist, Socrates was both existent and non-existent at the same time — existent through having become, non-existent by hypothesis. And if Socrates died, he died either when he lived or when he died. Now he did not die when he lived, since he would have been at once both alive and dead; nor yet when he died, since he would have been dead twice. Therefore Socrates did not die. And by applying this argument in turn to each of the things said to become or perish it is possible to abolish becoming and perishing.

— Sextus Empiricus

He was prettily and fantastically troubled, who, having used to put his trust in dreams, one night dreamed that all dreams were vain; for he considered, if so, then this was vain, and then dreams might be true for all this: but if they might be true, then this dream might be so upon equal reason: and then dreams were vain, because this dream which told him so was true; and so round again.

— Jeremy Taylor (1613–1667), “The Deceitfulness of the Heart”

“If the northern hemisphere were land, and all the southern hemisphere water, ought we to call the northern hemisphere an island, or the southern hemisphere a lake?” — Augustus De Morgan

In this conundrum by Mitsunobu Matsuyama, when four congruent quadrilaterals are rotated about their centers, their area seems to increase. What has become of the red square?

The answer is that each side of the large square is slightly shorter after the rotation. If θ is the angle between two opposing sides in each quadrilateral, then the ratio of the areas of the two large squares is sec² θ, about 0.8 percent when θ is 5°.