It is of no consequence whether a man of genius have learned either art or science before twenty-five: all that is necessary, or even desirable, is that his powers should be unfolded, his emulation roused, and his habits conducted into a right channel.

He has no right to his life when his duty calls him to resign it. Other men are bound... to deprive him of life or liberty, if that should appear in any case to be indispensably necessary to prevent a greater evil.

The mind of a child is no less vagrant than his steps; it pursues the gossamer and flies from object to object, lawless and unconfined, and it is equally necessary to the development of his frame that his thoughts and his body should be free from fetters.

There can be no passion, and by consequence no love, where there is not imagination.

Man is the interpreter of nature, science the right interpretation.

The ideas gained by men before they are twenty-five are practically the only ideas they shall have in their lives.