 |
 |
 |
 |
|
 |
 |
Hereditary Genius
xi
accomplished without a preliminary classification of ability according to a
standard scale, so the first part of the book is taken up with an attempt to
provide one.
The method employed is based on the law commonly known to
mathematicians as that of “frequency of error,” because it was devised by
them to discover the frequency with which various proportionate amounts
of error might be expected to occur in astronomical and geodetical
operations, and thereby to estimate the value that was probably nearest the
truth, from a mass of slightly discordant measures of the same fact.
Its application had been extended by Quetelet to the proportions of the
human body, on the grounds that the differences, say in stature, between
men of the same race might theoretically be treated as if they were Errors
made by Nature in her attempt to mould individual men of the same race
according to the same ideal pattern. Fantastic as such a notion may appear
to be when it is expressed in these bare terms, without the accompaniment
of a full explanation, it can be shown to rest on a perfectly just basis.
Moreover, the theoretical predictions were found by him to be correct, and
their correctness in analogous cases under reasonable reservations has
been confirmed by multitudes of subsequent observations, of which perhaps
the most noteworthy are those of Professor Weldon, on that humble
creature the common shrimp (Proc. Royal Society, p. 2, vol. 51, 1892).
One effect of the law may be expressed under this form, though it is not
that which was used by Quetelet. Suppose 100 adult Englishmen to be
selected at random, and ranged in the order of their statures in a row; the
statures of the 50th and the 51st men would be almost identical, and would
represent the average of all the
 |
|
 |
|