Who breaks a butterfly upon a wheel?

"Who breaks a butterfly upon a wheel?" is a quotation from Alexander Pope's "Epistle to Dr Arbuthnot" of January 1735.

It alludes to "breaking on the wheel", a form of torture in which victims had their long bones broken by an iron bar while tied to a Catherine wheel. The quotation is used to suggest someone is "[employing] superabundant effort in the accomplishment of a small matter".

The quotation is sometimes misquoted with "on" in place of "upon".

The line "Who breaks a butterfly upon a wheel?" forms line 308 of the "Epistle to Dr Arbuthnot" in which Alexander Pope responded to his physician's word of caution about making satirical attacks on powerful people by sending him a selection of such attacks. It appears in a section on the courtier John Hervey, 2nd Baron Hervey, who was close to Queen Caroline and was one of Pope's bitterest enemies. The section opens as follows:

Let Sporus tremble –"What? that thing of silk,
Sporus, that mere white curd of ass's milk?
Satire or sense, alas! can Sporus feel?
Who breaks a butterfly upon a wheel?
Yet let me flap this bug with gilded wings,
This painted child of dirt that stinks and stings;
Whose buzz the witty and the fair annoys,
Yet wit ne'er tastes, and beauty ne'er enjoys,

"Sporus", a male slave favoured by Emperor Nero, was, according to Suetonius, castrated by the emperor, and subsequently married. Pope here refers to accusations made in Pulteney's Proper reply to a late scurrilous libel of 1731 which led to Hervey challenging Pulteney to a duel. Hervey's decade-long clandestine affair with Stephen Fox would eventually contribute to his downfall. As first published the verse referred to Paris, but was changed to Sporus when republished a few months later.

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