In a foolishly bold or reckless manner; with a lack of proper caution or consideration.
Foolhardy plus the adverb suffix '-ly' (from Old English 'lice'). This adverbial form emerged naturally as English speakers needed to describe actions taken in a foolhardy way.
Foolhardily describes how many historical figures made their famous mistakes—not from stupidity, but from a kind of reckless confidence that looked like wisdom until it all went wrong spectacularly.
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