The profoundly wise do not declaim against superficial knowledge in others, as much as the profoundly ignorant.

A man who knows the world will not only make the most of everything he does know, but of many things that he does not know; and will gain more credit by his adroit mode of hiding his ignorance than the pendant by his awkward attempt to exhibit his erudition.

We owe almost all our knowledge not to those who have agreed, but to those who have differed

Knowledge is two-fold, and consists not only in an affirmation of what is true, but in the negation of that which is false.

That writer does the most who gives his reader the most knowledge and takes from him the least time

No company is far preferable to bad, because we are more apt to catch the vices of others than their virtues, as disease is more contagious than health.