A passage from Marcus Aurelius
Marcus Aurelius, Meditations 11.1
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These are the properties of the rational soul: it sees itself, analyses itself, and makes itself such as it chooses; the fruit which it bears itself enjoys.
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Men seek retreats for themselves, houses in the country, sea-shores, and mountains... But this is altogether a mark of the most common sort of men, for it is in thy power whenever thou shalt choose to retire into thyself.
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