thumb|right|upright=1.3|A man sits atop a dead horse in [[Sheboygan, Wisconsin. The idiom "to beat a dead horse" originated from the fact that flogging a dead horse will not compel it to do useful work.]]

Flogging a dead horse (or beating a dead horse in American English) is an idiom meaning that a particular effort is futile.

Early usage

The expression is said to have been popularized by the English politician and orator John Bright. Speaking in the House of Commons in March 1859 on Bright's efforts to promote parliamentary reform, Lord Elcho remarked that Bright had not been "satisfied with the results of his winter campaign" and that "a saying was attributed to him [Bright] that he [had] found he was 'flogging a dead horse'." Carrying out that work was said to be "working for a dead horse", since no additional benefit would be gained by the labourer when the work was complete.

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References

Further reading

  • File:En-au-flog a dead horse.ogg