The time comes in life when we have read enough. It's time to stop reading. It's time to lay down the books and write.

In the matter of physics, the first lessons should contain nothing but what is experimental and interesting to see. A pretty experiment is in itself often more valuable than twenty formulae extracted from our minds.

Earnestly I must exert myself in order to return as much as I have received.

Jesus is too colossal for the pen of phrasemongers, however artful. No man can dispose of Christianity with a bon mot

Despite my being an old gypsy there is a tendency to respectability inherent in old age.

The grand aim of all science is to cover the greatest number of empirical facts by logical deduction from the smallest number of hypotheses or axioms.

Rejoice with your family in the beautiful land of life.