A passage from Chrysippus
Chrysippus, Fragments (in Diogenes Laërtius) Lives 7.101
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The wise man is not free from the first movements of the soul, such as sudden fear or sudden desire, but he does not consent to them. For consent is in our power.
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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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Take away thy opinion, and then there is taken away the complaint, 'I have been harmed.' Take away the complaint, and the harm is taken away.
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At dawn, when you have trouble getting out of bed, tell yourself: 'I have to go to work — as a human being.'