Cum hoc ergo propter hoc 43
was quite clear. Neat handwriting correlated with large feet, with 99 per
cent probability that this was not mere chance.
(A teacher later told him that this was because older children tended
to write more neatly. Being older, they tended to have bigger feet.)Most disciplines which involve human measurement, includ-
ing economics and sociology, find cum hoes scattered liberally on
their domain. The reason for this is that we do not really know
what makes human beings act, so we look at their actions after
the fact and try to relate them to other events. The cum hoc tares
grow up with the wheat of genuine insights.
Elections make people spend. The figures are clear. Spending always
goes up in an election year.
(Could it be that governments seeking re-election tend to keep taxes
down in election years, and that people, in consequence, have more
to spend?)Deliberate use of the cum hoc ergo propter hoc is best made
with the support of reams of statistical information. Your audi-
ence, bemused by the figures, rarely have any of their own to set
against you. They can be made even more disposed to accept
the link which you are proposing if you cite the authority of
leading figures in the social sciences. This is easy. There is
nothing so absurd that it has not been attested to by such
people. It helps to be selective in your use of information.
Cun ownership is a major cause of violent crime. The prevalence of guns
in the US matches the high rates for crimes of violence. When violence is
contemplated, the guns are all too available.
(Excellent; but remember not to mention Switzerland, where almost
every household has a gun as part of military training. Switzerland
has low rates for violent crime, and the guns are almost never used.)