There is nothing in science which teaches the origin of anything at all.

Mathematics is the only true metaphysics.

Quaternions came from Hamilton after his really good work had been done, and though beautifully ingenious, have been an unmixed evil to those who have touched them in any way.

I have not the smallest molecule of faith in aerial navigation other than ballooning, or of the expectation of good results from any of the trials we heard of. So you will understand that I would not care to be a member of the Aeronautical Society.

When you cannot measure, your knowledge is meager and unsatisfactory.

[Referring to Fourier's mathematical theory of the conduction of heat] ... Fourier's great mathematical poem.

I have no satisfaction in formulas unless I feel their numerical magnitude.