To know that we know what we know, and that we do not know what we do not know, that is true knowledge.

I never found a companion that was so companionable as solitude.

I will come to you, my friend, when I no longer need you. Then you will find a palace, not an almshouse.

It is only when we forget all our learning that we begin to know.

True friendship can afford true knowledge. It does not depend on darkness and ignorance.

Books are the treasured wealth of the world and the fit inheritance of generations and nations. Books, the oldest and the best, stand naturally and rightfully on the shelves of every cottage. They have no cause of their own to plead, but while they enlighten and sustain the reader his common sense will not refuse them. Their authors are a natural and irresistible aristocracy in every society, and, more than kings or emperors, exert an influence on mankind.