Do not hover always on the surface of things, nor take up suddenly, with mere appearances; but penetrate into the depth of matters, as far as your time and circumstances allow, especially in those things which relate to your profession."

"Do not expect to arrive at certainty in every subject which you pursue. There are a hundred things wherein we mortals . . . must be content with probability, where our best light and reasoning will reach no farther."

"Acquire a government over your ideas, that they may come down when they are called, and depart when they are bidden."

"Tis the voice of the sluggard; I heard him complain,
You have wak'd me too soon, I must slumber again."

"What's amiss I'll strive to mend,
And endure what can't be mended."