No same man could walk through the same river twice, as the man and the river have since changed.

Hide our ignorance as we will, an evening of wine soon reveals it.

Heraclitus somewhere says that all things are in process and nothing stays still, and likening existing things to the stream of a river he says that you would not step twice into the same river.

No one can step twice into the same river, nor touch mortal substance twice in the same condition. By the speed of its change, it scatters and gathers again.

If you do not expect the unexpected, you will not recognize it when it arrives.

Change alone is unchanging.

All men have the capacity of knowing themselves and acting with moderation.