new facts, or indeed any facts. A school boy opens his copy of Xenophon’s Anabasis, and by reading the first sentence of the book he learns the fact, which (let us assume) is entirely new to him, that king Darius had two sons. He knows what particular fact is expressed by that particular sentence, although he never came across that sentence before and certainly did not know the fact before. He, therefore, cannot have learned that the one corresponds to the other. It is a necessary conclusion that the proposition and the fact which it expresses must naturally or essentially correspond to one another, they must have something in common. It is this common feature that we have to discover.
Nearly every day in our lives we learn the most important facts by looking at rows of little black marks of a very limited variety of shapes. And this variety can be reduced to an astonishing simplicity: The Morse alphabet manages to express any thought which has ever entered or ever will enter into any human mind by means of the simplest of signs, a dot and a dash.
How is this done? What makes expression possible? A first answer seems to present itself without difficulty: evidently it is the arrangement, the peculiar order or combination of signs which constitutes the essence of language. It is because a limited number of symbols can be arranged in an unlimited number of different ways that any set of symbols can be used to express any facts. I might use a chair in my room, for instance as a means of saying anything I like. All I need to do is to select a number of different positions of the chair in the room and agree that each one shall correspond to a letter of the alphabet. By this agreement I shall have constructed a new language which will consist in changing the position of the chair; and by moving it about in the room I shall be able to express all the plays of Shakespeare with the same perfection as the best of the printed editions.
The same set of signs which was used to describe a certain state of affairs can, by means of a rearrangement, be used to describe an entirely different state of affairs in such a way that we know the meaning of the new combination without having it explained to us. This last property is the important point which distinguishes Expression from mere Representation; it is the only essential point.
