When I have clarified and exhausted a subject, then I turn away from it, in order to go into darkness again.

As is well known the principle of virtual velocities transforms all statics into a mathematical assignment, and by D'Alembert's principle for dynamics, the latter is again reduced to statics. Although it is is very much in order that in gradual training of science and in the instruction of the individual the easier precedes the more difficult, the simple precedes the more complicated, the special precedes the general, yet the min, once it has arrived at the higher standpoint, demands the reverse process whereby all statics appears only as a very special case of mechanics.

Mathematics is the queen of the sciences.

The higher arithmetic presents us with an inexhaustible store of interesting truths - of truths, too, which are not isolated, but stand in a close internal connection, and between which, as our knowledge increases, we are continually discovering new and sometimes wholly unexpected ties.

It is not knowledge, but the act of learning, not possession but the act of getting there, which grants the greatest enjoyment.

You have no idea, how much poetry there is in the calculation of a table of logarithms!

Mathematical discoveries, like springtime violets in the woods, have their season which no human can hasten or retard.