What is Equivocation?

Equivocation means using words ambiguously. Often done with intent to deceive, it can even deceive the perpetrator. The fallacy of equivocation occurs when words are used with more than one meaning, even though the soundness of the reasoning requires the same use to be sustained throughout.


Happiness is the end of life.
The end of life is death;
So happiness is death.

(The form of the argument is valid, but ‘the end of life’ refers to its aim in the first line, and to its termination in the second. With this discovery, out go a million schoolboy conundrums.)

Half a loaf is better than nothing.
Nothing is better than good health;
So half a loaf is better than good health.

Equivocal use of words is fallacious because it invites us to transfer what we are prepared to accept about one concept onto another one which happens to have the same name. Logic, which processes the relationship between concepts, is useless if the concepts themselves change.

Elephants are not found in Britain, so if you have one, don’t lose it o will never find it again.

(The word ‘found’ represents two different concepts here.)


Many of the equivocal uses are easy to spot. Many more of them are not. Clairvoyants specialize in equivocal expressions to give them cover in the event of quite different outcomes. Politics would be a totally different art if it had to forego the fallacy of equivocation. So would business correspondence:


You can rest assured that your letter will receive the attention it f deserves.

(As it executes a gentle parabola towards the bin.)


‘Anyone who gets Mr Smith to work for him will indeed be fortunate.’


Puns and music-hall jokes often depend on this fallacy.


‘My dog’s got no nose. ‘
‘How does he smell?’


Calvin Coolidge was asked:

What do you think of the singer’s execution?

(He replied: ‘I’m all for it.’)


The advice given to a political candidate facing a selection committee is ‘When in doubt, equivocate.’ The blunt fact is that you cannot please all of the people all of the time, but you can have a good shot at fooling most of them for much of it. The candidate assures those in favour of capital punishment that he wants ‘realistic’ penalties for murder. To those against, he wants ‘humane consideration’. But he could be in favour of realistic light sentences or humane killing.

Equivocation is a particularly tough paste for pouring into the cracks of international discord. It joins irreconcilable differences with a smooth and undetectable finish. Many full and frank discussions are terminated happily by the appearance of a joint treaty whose wording is carefully chosen to mean entirely different things to each of the signatories.

The vocabulary of equivocation may be learned from the strangers’ gallery of the House of Commons. If you have a seat in the chamber, there is nothing you have to learn about it.

Once you have acquired the knack, and are fluent in phrases such as ‘having due regard for’, you can move on to the more subtle manifestations of the fallacy.


Well, it all depends on what you mean by full-hearted consent.

(You might have thought it obvious. You’d be wrong.)


The above article is from the book How To Win Every Argument by Madsen Pirie. The article is only for educational and informative purposes to explain and understand formal logic and logical fallacies. It is a great book, definitely worth a read!