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.

Beauty is no quality in things themselves: It exists merely in the mind which contemplates them; and each mind perceives a different beauty.

In all determinations of morality, this circumstance of public utility is ever principally in view; and wherever disputes arise, either in philosophy or common life, concerning the bounds of duty, the questions cannot, by any means, be decided with greater certainty, than by ascertaining, on any side, the true interests of mankind. If any false opinion, embraced from appearances, has been found to prevail; as soon as farther experience and sounder reasoning have given us juster notions of human affairs, we retract our first sentiment, and adjust anew the boundaries of moral good and evil.

The heights of popularity and patriotism are still the beaten road to power and tyranny.

We may conclude, therefore, that, in order to establish laws for the regulation of property, we must be acquainted with the nature and situation of man; must reject appearances, which may be false, though specious; and must search for those rules, which are, on the whole, most useful and beneficial.

When the coherence of the parts of a stone, or even that composition of parts which renders it extended; when these familiar objects, I say, are so inexplicable, and contain circumstances so repugnant and contradictory; with what assurance can we decide concerning the origin of worlds, or trace their history from eternity to eternity?

From the apparent usefulness of the social virtues, it has readily been inferred by sceptics, both ancient and modern, that all moral distinctions arise from education, and were, at first, invented, and afterwards encouraged ... in order to render men tractable, and subdue their natural ferocity and selfishness, which incapacitated them for society.