Power, like vanity, is insatiable. Nothing short of omnipotence could satisfy it completely. And as it is especially the vice of energetic men, the causal efficacy of love of power is out of all proportion to its frequency. It is, indeed, by far the strongest motive in the lives of important men.
Love of power is greatly increased by the experience of power, and this applies to petty power as well as to that of potentates.

What Desires Are Politically Important? (1950)