Tao Te Ching (Chapter 30)

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Whenever you advise a ruler in the way of Tao,
Counsel him not to use force to conquer the universe.
For this would only cause resistance.
Thorn bushes spring up wherever the army has passed.
Lean years follow in the wake of a great war.
Just do what needs to be done.
Never take advantage of power.
Achieve results,
But never glory in them.
Achieve results,
But never boast.
Achieve results,
But never be proud.
Achieve results,
Because this is the natural way.
Achieve results,
But not through violence.

Force is followed by loss of strength.
This is not the way of Tao.
That which goes against the Tao comes to an early end.

Tao Te Ching (Chapter 30), by Lao Tzu.