Secundum quid 145
Secundum quid
The fallacy of secundum quid is otherwise known as the hasty
generalization. Whenever a generalization is reached on the basis
of a very few and possibly unrepresentative cases, the fallacy is
committed. It takes the argument from particular cases to a
general rule on the basis of inadequate evidence.
/ was in Cambridge for ten minutes and I met three people, all drunk.
The whole place must be in a state of perpetual inebriation.
(Not necessarily so. Saturday night outside Trinity College might be
quite different from King's on Sunday. A similar conclusion about
London might have been drawn by a visitor who saw three people at
midday outside a newspaper office.)The fallacy lies in the assumption of material which ought to
be established. There should be an attempt to establish that the
sample is sufficiently large and sufficiently representative. One or
two cases in particular circumstances do not justify the pre-
sumption of a general rule, any more than the sight of a
penny coming down heads can justify a claim that it will always
do so.
Behind our identification of the fallacy lies our recognition
that the few cases observed might be exceptional to any general
rule which prevails.
Don't shop there. I once bought some cheese and it was mouldy.
(This smells like a broad condemnation placed on a narrow base.)Clearly there is fine judgement required to distinguish
between a secundum quid and a case where one or two instances
do enable a valid judgement to be made. When assessing the