When Darius offered him ten ...

When Darius offered him ten thousand talents, and to divide Asia equally with him, \
When Darius offered him ten thousand talents, and to divide Asia equally with him, "I would accept it," said Parmenio, "were I Alexander." "And so truly would I," said Alexander, "if I were Parmenio." But he answered Darius that the earth could not bear two suns, nor Asia two kings.

Quotes from the same author

Silence at the proper season is wisdom, and better than any speech.
Know how to listen, and you will profit even from those who talk badly.
To make no mistakes is not in the power of man; but from their errors and mistakes the wise and good learn wisdom for the future.
I don't need a friend who changes when I change and who nods when I nod; my shadow does that much better.
What we achieve inwardly will change outer reality.