Tu quoque 165And now I turn to Mrs Green's charge that I deliberately misled this
society over my personal interest in the firm concerned. May I remind you
that this charge comes from the same Mrs Green who kept very quiet
when her son-in-law benefited from our decision over the surplus land.
Hardly a source entitled to make such charges, you must agree.
(I reckon he did it.)The fallacy of the tu quoque occurs because it makes no
attempt to deal with the subject under discussion. A new subject
is introduced, namely the record of someone involved. The truth
or falsehood of an assertion has nothing to do with the back-
ground of the person who makes it. Evidence for or against that
assertion is not altered by details of the previous actions of the
one who is putting it forward.
Another version of the tu quoque seeks to undermine what is
being said by showing it to be inconsistent with the previous
views of its proposer.
Why should we listen to Brown's support for the new carpark when only
last year he opposed the whole idea?
(For one thing, if the arguments changed his mind they might be
worth listening to. For another, there might be more cars around.)Because someone once opposed an idea it does not preclude
their arguments in favour from being good ones. Despite this,
the fallacy is supported by a strong tendency in us to appear
consistent whenever we can. The new mayor finds it difficult to
argue with sincerity this year in favour of the same official
limousine which he opposed so vociferously for his predecessor.
The UK's parliamentary question-time is the home of the tu
quoque. Indeed, skill at handling questions is often measured
exclusively in terms of the performer's dexterity with this