When the mind or ruling principle is properly regulated, it can with ease and at any time adapt itself to the various events of life, which are presented to it for the subject of its operations. For it is not particularly attached to any one subject or mode of action. It exerts itself with a preference indeed on things more agreeable, but with a reserve of acquiescence; and if chance throw anything of a contrary quality in its way, it takes that for the subject of its philosophy to work upon; which, like a strong fire, converts and assimilates that to its own substance, which would extinguish a slight flame, triumphs over all resistance, and becomes more brilliant by this addition of combustible matter.

Marcus Aurelius, Meditations
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