Augustus De Morgan

I end with a word on the new symbols which I have employed. Most writers on logic strongly object to all symbols. . . I should advise the reader not to make up his mind on this point until he has well weighed two facts which nobody disputes, both separately and in connexion. First, logic is the only science which has made no progress since the revival of letters; secondly, logic is the only science which has produced no growth of symbols.

Every science that has thriven has thriven upon its own symbols: logic, the only science which is admitted to have made no improvements in century after century, is the only one which has grown no symbols.

It is easier to square the circle than to get round a mathematician.

[When asked about his age.] I was x years old in the year x^2.