Forms: 5–7 falacy(e, 6–7 fallacie, (7 fallecie), 7– fallacy. [ad. L. fallācia, n. of quality f. fallax deceptive: see FALLACE a. First in 15th c. replacing the older FALLACE sb.]
† 1. Deception, guile, trickery; a deception, trick; a false statement, a lie. Obs.
1481. Caxton, Reynard (Arb.), 67. Ha reynart how wel can ye your falacye and salutacion doon.
1607. Topsell, Four-f. Beasts (1673), 159. Then make they a narrow bridge covered with earth … that the beasts may dread no fallacy.
1671. Milton, P. R., I. 155.
| Winning by Conquest what the first man lost | |
| By fallacy surprized. |
1740. Fielding, Tom Jones, XVI. ix. Her utter detestation of all fallacy.
2. † a. Deceitfulness (obs.). b. Deceptiveness, aptness to mislead, unreliability.
1641. J. Johnson (title), The Academy of Love, describing the Folly of younge Men and the Fallacy of Women.
1654. R. Whitlock, Ζωοτομια, 220. Let us not affirm their existence, and ὅτι on the Fallacies of Sense.
c. 1800. K. White, Rem. (1837), 381. The fallacy of human friendship.
1849. Mrs. Somerville, Connex. Phys. Sc., xxv. 264. A consciousness of the fallacy of our senses.
3. A deceptive or misleading argument, a sophism. In Logic esp. a flaw, material or formal, that vitiates a syllogism; any of the species or types to which such flaws are reducible. Also, sophistical reasoning, sophistry.
Not in Wilson’s Logic (1552) which has ‘deceipt,’ ‘deceiptfulness,’ as the equivalent of fallacia in this sense.
1562. Turner, Herbal, II. 100 a. It is a false fallacie … to argue from a parte to the hole.
1612. Brinsley, Lud. Lit., xvii. (1627), 208. To helpe to answere the subtilties or fallacies.
a. 1665. J. Goodwin, Πλήρωμα τὸ Πνευματικόν; or, A Being Filled with the Spirit (1867), 160. I shall … proceed to shew the fallacies and other weaknesses of those pretences, wherein our adversaries rejoice so much as if they were arguments above answer.
1776. Adam Smith, W. N., II. iv. I. 357. The fallacy which seems to have misled those gentlemen.
1884. Bosanquet, trans. Lotze’s Logic, 284. The commonest fallacy is ambiguity of the middle term, quaternio terminorum or fallacia falsi medii more or less disguised.
4. A delusive notion, an error, esp. one founded on false reasoning. Also, the condition of being deceived, error.
1590. Shaks., Com. Err., II. ii. 188. Ile entertaine the free’d [Globe ed., offer’d] fallacie.
1665. Glanvill, Scepsis Scientifica, xiii. 75. We being then thus obnoxious to fallacy in our apprehensions and judgments, and so often imposed upon by these deceptions, our Inferences and Deductions must needs be as unwarrantable, as our simple and compound thoughts are deceitful.
1735–8. Bolingbroke, On Parties, Ded. 22. When They cannot impose a Fallacy, endeavour … to hinder Men from discerning a Truth.
1825. Syd. Smith, Wks. (1859), II. 59/2. There are a vast number of absurd and mischievous fallacies, which pass readily in the world for sense and virtue, while in truth they tend only to fortify error and encourage crime.
1844. H. H. Wilson, Brit. India, I. 413. In adducing the authority of Hindu writers in favour of the doctrine, two sources of fallacy are discernible.
5. Sophistical nature, unsoundness (of arguments); erroneousness, delusiveness (of opinions, expectations, etc.).
1777. Priestley, Disc. Philos. Necess., Pref. 30. I was enabled to see the fallacy of most of the arguments.
1825. M’Culloch, Pol. Econ., II. 158. The returns under the population acts have shown the fallacy of these opinions.
1850. Prescott, Peru, II. 193. Expectations of wealth, of which almost every succeeding expedition had proved the fallacy.
† b. Proneness to err, fallibility. Obs. rare.
1651. N. Bacon, Discourse of the Laws & Government of England, II. xxvii. (1682), 120. Then finding the fallacy of the infallible Chair, he hearkens unto other Doctors.
1796. Gouv. Morris, in Sparks, Life & Writ. (1832), III. 87. Experience has taught me a sincere faith in the fallacy of human opinions, and more especially of my own.
6. Comb., as fallacy-monger.
1849. Cobden, Speeches, 10. When the revolutions broke out, these fallacy-mongers exclaimed, ‘Here’s Cobden, just come back from the Continent, tells us the people are all for peace—now they are all for war.’
