A mind at liberty to reflect on its own observations, if it produce nothing useful to the world, seldom fails of entertainment to itself.

To be is to be perceived

But the velocities of the velocities - the second, third, fourth, and fifth velocities, etc. - exceed, if I mistake not, all human understanding.

I had rather be an oyster than a man, the most stupid and senseless of animals.

From my own being, and from the dependency I find in myself and my ideas, I do, by an act of reason, necessarily infer the existence of a God, and of all created things in the mind of God.

There being in the make of an English mind a certain gloom and eagerness, which carries to the sad extreme; religion to fanaticism; free-thinking to atheism; liberty to rebellion.

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