Isaac Newton — "The best way to understand is by examples."

"I do not define time, space, place, and motion, as being well known to all."

"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."

"Every body continues in its state of rest, or of uniform motion in a right line, unless it is compelled to change that state by forces impressed upon it."

"The best and safest method of philosophizing seems to be, first to inquire diligently into the properties of things, and to establish those properties by experiments, and then to proceed more slowly t…"

"No great discovery was ever made without a bold guess."