46 THE MISMEASURE OF MAN
surpassed 250,000 copies, plus translations into ten languages. I
have been particularly gratified by the warm and challenging corre-
spondence that has continually come my way (and at least amused
by some of the hate mail, including a few threats from neo-Nazis
and anti-Semites). I am particularly glad, in retrospect, that I chose
to write in a way that surely precluded maximal eclat at publication
(as a breezier style with more references to immediate issues would
have accomplished), but that gave the book staying power (a focus
on founding arguments, analyzed by consulting original sources in
their original languages).
The Mismeasure of Man is not easy reading, but I intended the
book for all serious people with interest in the subject. I followed
the two cardinal rules that I use in writing my essays. First, do not
waffle on about generalities (as I fear I have done a bit in this intro-
duction—sins of my middle age, no doubt!). Focus on those small,
but fascinating, details that can pique people's interest and illustrate
generalities far better than overt and tendentious discussion. This
strategy provides a better book for readers, but also makes the com-
position so much more fun for me. I got to read all the original
sources; I had all the pleasure of poking into Broca's data and find-
ing the holes and unconscious prejudices, of reconstructing Yerkes's
test to army recruits, of hefting a skull filled with lead shot. How
much more rewarding than easy reliance on secondary sources, and
copying a few conventional thoughts from other commentators.
Second, simplify writing by eliminating jargon, of course, but
do not adulterate concepts; no compromises, no dumbing down.
Popularization is part of a great humanistic tradition in serious
scholarship, not an exercise in dumbing down for pleasure or profit.
I therefore did not shy from difficult, even mathematical material.
Since I've been holding back for fifteen years, permit me a few
paragraphs for pure bragging and saying what has pleased me most
about the book.
The history of mental testing in the twentieth century has two
major strands: scaling and ranking by mental age as represented
by IQ testing, and analysis of correlations among mental tests as
manifested in factor analysis. Effectively every popular work on
mental testing explains the IQ thread in detail and virtually ignores
factor analysis. This strategy is followed for an obvious and under-
standable reason: the IQ story is easy to explain and comprehend;