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The art of life is more like the wrestler's art than the dancer's, in respect of this, that it should stand ready and firm to meet onsets which are sudden and unexpected.
— Marcus Aurelius · Meditations

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
Life is compared with a wrestler’s readiness to meet sudden attacks, rather than a dancer’s art. The point is firmness in facing the unexpected, not a requirement to fight another person.
Context reviewed