The grape that can with logic absolute,
The Two-and-Seventy Sects confute.
Other poets and writers have had much to say on the subject of logic through the years, words of tribute and words of warning. Some, like Lord Dunsany, counsel moderation even in our logic. “Logic, like whiskey,” he says, “loses its beneficial effect when taken in too large quantities.” And Oliver Wendell Holmes asks,
Have you heard of the wonderful one-hoss shay
That was built in such a logical way
It ran a hundred years to the day?
The words logic and logical are much used and abused in our language, and there are all sorts of logic, including that of women, which seems to be a special case. For our purposes here it is best to stick to the primary definition in the dictionary, that of validity in thought and demonstration.
Symbolic logic, a term that still has an esoteric and almost mystical connotation, is perhaps mysterious because of the strange symbology used. We are used to reasoning in words and phrases, and the notion that truth can be spelled out in algebraic or other notation is hard to accept unless we are mathematicians to begin with.
We must go far back in history for the beginnings of logic. Aristotelian logic is well known and of importance even though the old syllogisms have been found not as powerful as their inventors thought. Modern logicians have reduced the 256 possible permutations to a valid 15 and these are not as useful as the newer kind of logic that has since come into being.
Leibniz is conceded to be the father of modern symbolic logic, though he probably neither recognized what he had done nor used it effectively. He did come up with the idea of two-valued logic, and the cosmological notion of 1 and 0, or substance and nothingness. In his Characteristica Universalis he was groping for a universal language for science; a second work, Calculus Ratiocinator, was an attempt to implement this language. Incidentally, Leibnitz was not yet twenty years old when he formulated his logic system.