No amount of observations of white swans can allow the inference that all swans are white, but the observation of a single black swan is sufficient to refute that conclusion.

A CAUSE is an object precedent and contiguous to another, and so united with it that the idea of the one determines the mind to form the idea of the other, and the impression of the one to form a more lively idea of the other.

The great subverter of Pyrrhonism or the excessive principles of scepticism is action, and employment, and the occupations of common life.

Riches are valuable at all times, and to all men, because they always purchase pleasures such as men are accustomed to and desire; nor can anything restrain or regulate the love of money but a sense of honor and virtue, which, if it be not nearly equal at all times, will naturally abound most in ages of knowledge and refinement.

Of all sciences there is none where first appearances are more deceitful than in politics.

.. that which renders morality an active principle and constitutes virtue our happiness, and vice our misery: it is probable, I say, that this final sentence depends on some internal sense or feeling, which nature has made universal in the whole species.

The fact that different cultures have different practices no more refutes [moral] objectivism than the fact that water flows in different directions in different places refutes the law of gravity