If you have never failed, you have never tried anything new.

Marvellous, what ideas the young people have these days. But I don't believe a word of it.

...and knowledge is one of the finest attributes of man - though often it is most loudly voiced by those who strive for it the least.

[Newton wrote to Halley ... that he would not give Hooke any credit] That, alas, is vanity. You find it in so many scientists. You know, it has always hurt me to think that Galileo did not acknowledge the work of Kepler.

I believe that I have really found the relationship between gravitation and electricity, assuming that the Miller experiments are based on a fundamental error. Otherwise, the whole relativity theory collapses like a house of cards.

Something deeply hidden had to be behind things.

In the beginning (if there was such a thing), God created Newton's laws of motion together with the necessary masses and forces. This is all; everything beyond this follows from the development of appropriate mathematical methods by means of deduction.