Letters 3.5

In like manner you should rebuke these two kinds of men,—both those who always lack repose, and those who are always in repose. For love of bustle is not industry,—it is only the restlessness of a hunted mind. And true repose does not consist in condemning all motion as merely vexation; that kind of repose is slackness and inertia.

Seneca, Letters to Lucilius 3.5, translated by Richard Mott Gummere