It is not that pearls fetch a high price because men have dived for them; but on the contrary, men have dived for them because they fetch a high price.

An instinct is a blind tendency to some mode of action, independent of any consideration, on the part of the agent, of the end to which the action leads.

The best security against revolution is in constant correction of abuses and the introduction of needed improvements. It is the neglect of timely repair that makes rebuilding necessary.

As a science, logic institutes an analysis of the process of the mind in reasoning, and investigating the principles on which argumentation is conducted; as an art, it furnishes such rules as may be derived from those principles, for guarding against erroneous deductions.

The Eastern monarch who proclaimed a reward to him who should discover a new pleasure, would have deserved well of mankind had he stipulated that it should be blameless.

The word of knowledge, strictly employed, implies three things: truth, proof, and conviction.

He who is not aware of his ignorance will be only misled by his knowledge.