All those who write either explicitly or by insinuation against the dignity, freedom, and immortality of the human soul, may so far forth be justly said to unhinge the principles of morality, and destroy the means of making men reasonably virtuous.

That neither our thoughts, nor passions, nor ideas formed by the imagination, exist without the mind, is what every body will allow.

This perceiving, active being is what I call mind, spirit, soul, or myself. By which words I do not denote any one of my ideas, but a thing entirely distinct from them, wherein they exist, or, which is the same thing, whereby they are perceived; for the existence of an idea consists in being perceived.

In short, if there were external bodies, it is impossible we should ever come to know it; and if there were not, we might have the very same reasons to think there were that we have now.

Whatever the world thinks, he who hath not much meditated upon God, the human soul, and the summum bonum, may possibly make a thriving earthworm, but will most indubitably make a sorry patriot and a sorry statesman.

All men have opinions, but few think.

The method of Fluxions is the general key by help whereof the modern mathematicians unlock the secrets of Geometry, and consequently of Nature.