From Marcus Aurelius Book 3
“13. Just as physicians always keep their lancets and instruments ready to their hands for emergency operations, so also do thou keep thine axioms ready for the diagnosis of things human and divine, and for the performing of every act, even the pettiest, with the fullest consciousness of the mutual ties between these two. For thou shalt never carry out well any human duty unless thou correlate it to the divine, nor the reverse.”
- Excerpt From: Emperor of Rome Marcus Aurelius. “Meditations.” Book # III
First use of this quote? Different translation, same verse.Marcus Aurelius (Loeb Classical Library)
Delphi Complete Works of Marcus Aurelius – Marcus Aurelius
Meditations – Marcus Aurelius & Gregory HaysMeditations: A New Translation (Modern Library)
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