What doubts, what hypotheses, what labyrinths of amusement, what fields of disputation, what an ocean of false learning, may be avoided by that single notion of immaterialism!

The love of truth, virtue, and the happiness of mankind are specious pretexts, but not the inward principles that set divines at work; else why should they affect to abuse human reason, to disparage natural religion, to traduce the philosophers as they universally do?

But, say you, surely there is nothing easier than for me to imagine trees, for instance, in a park [. . .] and nobody by to perceive them. [...] The objects of sense exist only when they are perceived; the trees therefore are in the garden [. . .] no longer than while there is somebody by to perceive them.

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.

To be is to be perceived (Esse est percipi)." Or, "If a tree falls in the forest and no one is there to hear it, does it make a sound?

Westward the course of empire takes its way; The four first acts already past, A fifth shall close the drama with the day: Time's noblest offspring is the last.

Many things, for aught I know, may exist, whereof neither I nor any other man hath or can have any idea or notion whatsoever.