Language as Set Theory

The revolution in our understanding of the logic of names began with a basic question: Where do the meanings of words live? There are two likely habitats. One is the world, where we find the things that a word refers to. The other is in the head, where we find people’s understanding of how a word may be used. For anyone interested in language as a window into the mind, the external world might seem to be an unpromising habitat. The word cat, for example, refers to the set of all the cats t...

 When Politics Gives Way to Physics

People who take pride in the same object can form a knightly order but not a brotherhood of loving sons. However, as soon as pride in the exploits of the fathers is replaced by grief over their death, we will begin to perceive the Earth as a graveyard and nature as a death-bearing force. Then politics will yield to physics, which cannot be separated from astronomy. Then the Earth will be seen as a heavenly body and the stars as so many earths. The convergence of all sciences in astronomy is a...

 The Magnet Was An Accidental Discovery

So again, if, before the discovery of the magnet, anyone had said that a certain instrument had been invented by means of which the quarters and points of the heavens could be taken and distinguished with exactness, men would have been carried by their imagination to a variety of conjectures concerning the more exquisite construction of astronomical instruments; but that anything could be discovered agreeing so well in its movements with the heavenly bodies, and yet not a heavenly body itself...