To be is to be perceived

The table I write on I say exists ... meaning thereby that if I was in my study I might perceive it, or that some other spirit actually does perceive it.

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

[Christianity] neither enjoins the nastiness of the Cynic, nor the insensibility of the Stoic.

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?

Our youth we can have but to-day, We may always find time to grow old.

Of all men living [priests] are our greatest enemies. If it were possible, they would extinguish the very light of nature, turn the world into a dungeon, and keep mankind for ever in chains and darkness.