Theories are usually the over-hasty efforts of an impatient understanding that would gladly be rid of phenomena, and so puts in their place pictures, notions, nay, often mere words.

On top of the world, or in the depths of despair.

Everything in science depends on what one calls an aperçu, on becoming aware of what is at the bottom of the phenomena. Such becoming aware is infinitely fertile.

Conscience is the virtue of the observers not the agents of action

Daily life is more instructive than the most effective book.

Oh how sweet it is to hear one's own convictions from another's lips.

It is a misfortune to pass at once from observation to conclusion, and to regard both as of equal value; but it befalls many a student.