Sociology is the science with the greatest number of methods and the least results.

Mathematicians do not study objects, but the relations between objects.

Mathematicians do not study objects, but relations among objects; they are indifferent to the replacement of objects by others as long the relations don't change. Matter is not important, only form interests them.

It may happen that small differences in the initial conditions produce very great ones in the final phenomena.

Mathematical discoveries, small or great are never born of spontaneous generation.

Einstein does not remain attached to the classical principles, and when presented with a problem in physics he quickly envisages all of its possibilities. This leads immediately in his mind to the prediction of new phenomena which may one day be verified by experiment.

Geometry is not true, it is advantageous.