the.com/madman

The highest compliment for a plan too ambitious to have come from a sane person.

means A man whose mind has become deranged or who acts with wild, uncontrolled irrationality — though today it's often slung affectionately at anyone whose brilliance looks indistinguishable from lunacy.

from Straightforward Old English carpentry: 'mad,' from gemǣd meaning out of one's mind or senseless, bolted onto 'man.' The word has barely changed shape in a thousand years — its drift has been entirely in tone, sliding from clinical dread toward the backhanded awe of calling a wild idea 'madness' you secretly admire.

origin
literally just means lunatic, repurposed as praise
usage
deployed right before someone attempts something reckless and brilliant
tone
admiration disguised as concern for their mental health
classic line
he actually did it, the madman
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