Although every novel is derived directly from another novel, there is really only one novel, the Quixote.

Aristotelian logic is massive and marmoreal, but every monument accumulates graffiti.

Although every novel is derived directly from another novel, there is really only one novel, the Quixote.

In the end, every scheme and every science is justified by itself or it is not justified at all.

I do not know whether any of this is true. I am certain that the scientific community does not know that it is false.

More than sixty years ago, mathematical logicians, by defining precisely the concept of an algorithm, gave content to the ancient human idea of an effective calculation. Their definitions led to the creation of the digital computer, an interesting example of thought bending matter to its ends.

The world of shapes, lines, curves, and solids is as varied as the world of numbers, and it is only our long-satisfied possession of Euclidean geometry that offers us the impression, or the illusion, that it has, that world, already been encompassed in a manageable intellectual structure. The lineaments of that structure are well known: as in the rest of life, something is given and something is gotten; but the logic behind those lineaments is apt to pass unnoticed, and it is the logic that controls the system.