Power acquired by violence is only a usurpation, and lasts only as long as the force of him who commands prevails over that of those who obey.
Interpretation
Violent power is illegitimate and unstable, reliant on force rather than true authority.
Denis Diderot's quote emphasizes that power gained through violence is not legitimate; it is merely a seizure of control that can easily crumble when the coercive force is diminished. True authority is built on consent and the willingness of others to follow rather than through intimidation or fear.
In practice
In a speech on leadership, you might quote Diderot to emphasize the importance of ethical governance.
The arbitrary rule of a just and enlightened prince is always bad. His virtues are the most dangerous and the surest form of seduction: they lull a people imperceptibly into the habit of loving, respecting, and serving his successor, whoever that successor may be, no matter how wicked or stupid.
This root [the potato], no matter how much you prepare it, is tasteless and floury. It cannot pass for an agreeable food, but it supplies a food sufficiently abundant and sufficiently healthy for men who ask only to sustain themselves. The potato is criticized with reason for being windy, but what matters windiness for the vigorous organisms of peasants and laborers?
Do you see this egg? With this you can topple every theological theory, every church or temple in the world.
There are three principal means of acquiring knowledge... observation of nature, reflection, and experimentation. Observation collects facts; reflection combines them; experimentation verifies the result of that combination.
In order to get as much fame as one's father one has to much more able than he.
All abstract sciences are nothing but the study of relations between signs.
Totalitarian states killed with impunity and no one was held accountable. That didn't happen in the West.
Anxiety is the dizziness of freedom.
Experience having long taught me the reasonableness of mutual sacrifices of opinion among those who are to act together for any common object, and the expediency of doing what good we can; when we cannot do all we would wish.
'Thou shalt not kill' does not apply to murder of one's own kind only, but to all living beings and this commandment was inscribed in the human breast long before it was proclaimed from Sinai.
The big message of gospel is that you don't have to keep fighting the universe; you can stop, and the universe is quite good to you. There is a loss of ego.
There is no space in which worship should not take place, no time when it should not occur, and no activity through which it should not happen.
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