Mathematics are well and good but nature keeps dragging us around by the nose.

Do not worry about your problems with mathematics, I assure you mine are far greater.

Since the mathematicians have invaded the theory of relativity I do not understand it myself any more.

We still do not know one thousandth of one percent of what nature has revealed to us.

Pure mathematics is, in its way, the poetry of logical ideas.

Fortunate Newton, happy childhood of science. Nature to him was an open book. He stands before us strong, certain, and alone.