“If a cluttered desk is a sign of a cluttered mind, of what, then, is an empty desk a sign?”
Quote Investigator turned up nothing with respect to the above. Beware of all attributions, especially those to the great physicist. But the thought's the thing regardless of who said it or wrote it.
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Pseudo-Latin French Bullshit: The Cartesian Castle
On Diachronic or 'Emersonian' Consistency