Adynata

Adynaton (plural adynata) is a figure of speech in the form of hyperbole taken to such extreme lengths as to insinuate a complete impossibility:

The word derives from the Greek ἀδύνατον (adunaton), neuter of ἀδύνατος (adunatos), "unable, impossible" (a-, "without" + dynasthai, "to be powerful").

Adynaton was a widespread literary and rhetorical device during the Classical Period. In the Eclogue of Plutarch, there is a long list of proverbs and the first section is titled ΠΕΡΙ ΤΩΝ ΑΔΥΝΑΤΩΝ, consisting of proverbs that are built on adynaton. The adynaton form was often used for vows and covenants, such as in the 16th Epode of Horace, 25-34.

Its plural form (adynata) was translated in Latin as impossibilia. A frequent usage was to refer to one highly unlikely event occurring sooner than another:

Zenobius's collection of proverbial expressions includes "to count sand" to characterize something impossible or unattainable.

However it largely fell into disuse during the Middle Ages before undergoing a minor revival in the works of romantic poets, who would boast of the power of their love, and how it could never end.

Adynata are sometimes used within works of fiction or drama:

Impossible tasks appear often in legends and folklore, and can form elements of ballads, riddles and proverbs. Examples include: the tale of "The Spinning-Woman by the Spring",

Some modern adynata include:

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