The Mountain in Labour is one of Aesop's Fables and appears as number 520 in the Perry Index. The story became proverbial in Classical times and was applied to a variety of situations. It refers to speech acts which promise much but deliver little, especially in literary and political contexts. In more modern times the satirical intention behind the fable was given greater emphasis following Jean de la Fontaine's interpretation of it. Illustrations to the text underlined its ironical application particularly and went on to influence cartoons referring to the fable elsewhere in Europe and America.
The Classical fable
The earliest surviving version of the tale is in a four-line Latin poem by Phaedrus:
"A mountain was in labour, uttering immense groans, and on earth there was very great expectation. But it gave birth to a mouse. This has been written for you, who, though you threaten great things, accomplish nothing."
But the most well-known mention of the fable appears in Horace's epistle on The Art of Poetry. Discussing what to avoid in a poem's opening, he recommends a writer not to begin an epic poem in too grandiose a way, to avoid what follows being an anticlimax:
And don’t start like an old writer of epic cycles once did: "Of Priam’s fate I’ll sing, and the greatest of Wars." What could he produce to match his opening promise? Mountains will labour: what’s born? A ridiculous mouse! (Ars Poetica, 136–9)
Some editions of the poem have the present tense instead of the future . The future is found in all the chief manuscripts and also in quotations of the line in Probus, Servius, and Jerome. Despite this, Richard Bentley preferred to read , arguing that like other verbs ending in -urio the present tense already has an inherently future meaning ("they wish to give birth", "they are about to give birth"). However, A. S. Wilkins in his edition defends the future tense , explaining the line as meaning "if you do begin so, it will be a case of 'Mountains in labour, and out comes a mouse'."
A number of writers of Greek origin also alluded to the fable. Plutarch described it as an "old proverb", and the Latin grammarian Porphyrio claimed that it was a Greek proverb that Horace had been quoting. One early version of the proverb in Greek is the following, which is quoted by Athenaeus:
"A mountain was in labour, and Zeus was scared; but it gave birth to a mouse."
The Greek verse above, in the Sotadean metre, was supposedly said by the 4th-century BC Egyptian King Tachōs to the Spartan king Agesilaus, mocking him for his small stature. Agesilaus is said to have replied "One day I will appear to you like a lion!"
The verse is discussed in an article by Howard Jacobson (2007), in which he argues that the original proverb may have meant "she was in labour with a mountain, but in the end produced only a mouse".
Mediaeval interpretations
During the Middle Ages the fable was retold many times without significant variation. The moral, however, was differently expressed and widened to specify a variety of circumstances to which it could be applied.
One of the Anglo-Latin prose collections going under the name Romulus gives a more extended interpretation, commenting that it warns one not to believe big talk, "for there are some who promise many more things than they deliver, and some who threaten much and perform least". This was more or less the conclusion on which William Caxton closed his ambiguous adaptation of the story as "a hylle whiche beganne to tremble and shake by cause of the molle whiche delved hit". There was, however, a closer English-language version of the fable told earlier by John Gower in his Confessio Amantis (c.1390), with the advice not to be taken in by every empty rumour.
The actual line from Horace's poem (Parturient montes, nascetur ridiculus mus) was reproduced word for word in another mediaeval compilation of fables, the Ysopet-Avionnet. In this instance, however, the allusion was in connection with the different fable about Belling the cat, which has as subject the ineffectiveness of political dialogue.