[42] thing in common: they point beyond themselves. The sound of the word "desk" points to the thing "desk," which I can also touch, look at, smell, and throw away, if I am angry. In this sense a sign^a points beyond itself. There are other signs where this is very clear; for instance, there are signs which are very important because they are matters of life and death for all of us, namely the signs at the street corner: "red" and "green." But they are signs, they are not symbols; they point to something else. "Green" means "GO" and "red" means "STOP." But "greenhood" and "going", and "redhood" and "stopping," have nothing to do with each other. This means this is a mere matter of expediency and convention. For expedient reasons, convention has decided to use these lights for these different purposes. In this way signs are always matters of convention, and conventional products can also be changed, removed, you can do with them whatever you want, if there is a sufficient support from those who decide about what shall be valid conventionally and what not. Now this is one main difference between signs and symbols. Signs^b are matters of expediency and convention; symbols^c are produced in a creative process which goes down to the unconscious--and, if I could use the phrase without danger of being criticized as a wild-going [?] realist and not nominalist, then I would even use Jung's term "collective unconscious"--but l use it with reservation. It cannot be invented, therefore, and removed by decisions from the point of view of expediency. It grows, and it may die. Signs are invented and removed; symbols grow and die. This means something even more important. It means that symbols^d participate in the power of that which they symbolize; signs^e do not. The letter "A" does not participate in the sound "A". They have nothing to do with each other. In many alphabets the sound is quite different, and the letter is different for the same sound. This is a matter of convention. And the sound "M" or "P", used in mathematics, could have been different and can be changed if a congress of mathematicians of the world would decide [so]. They don’t decide about the older signs, which are now so much used that it would be almost a catastrophe to change them. But if something new comes out, someone suggests, "Let us call it 'I'--[?] (one of the most mystical mathematical signs) [?]--the others follow and convention is established. Others could say "No, there is something better," and they don’t follow. But if a symbol has grown, you cannot do that with it.