Solitude, though it may be silent as light, is like light, the mightiest of agencies; for solitude is essential to man. All men come into this world alone and leave it alone.

The whole body of the arts and sciences composes one vast machinery for the irritation and development of the human intellect.

Grief! thou art classed amongst the depressing passions. And true it is that thou humblest to the dust, but also thou exaltest to the clouds. Thou shakest us with ague, but also thou steadiest like frost. Thou sickenest the heart, but also thou healest its infirmities.

Under our present enormous accumulation of books, I do affirm that a most miserable distraction of choice must be very generally incident to the times; that the symptoms of it are in fact very prevalent, and that one of the chief symptoms is an enormous 'gluttonism' for books.

I feel that there is no such thing as ultimate forgetting; traces once impressed upon the memory are indestructible.

A promise is binding in the inverse ratio of the numbers to whom it is made.

All parts of knowledge have their origin in metaphysics, and finally, perhaps, revolve into it.