Isaac Newton — "If I am anything, which I highly doubt, it is due to hard work."

"Gravity must be caused by some agent acting constantly according to certain laws; but whether this agent be material or immaterial, I have left to the consideration of my readers."

"Nature is pleased with simplicity."

"It is the perfection of God's works that they are all done with the greatest simplicity."

"He that in the study of natural philosophy shall resolve to proceed upon nothing but demonstrations and sound knowledge, hath a very large field of materials of all sorts to divert and employ him."

"It is the weight, not numbers of experiments that is to be regarded."