essary that every part in an
individual should be useful to the other parts and to the whole animal?
Should it not be enough that they do not injure each other nor stand in
the way of each other's fair development? All parts coexist which do not
injure each other enough to destroy each other, and perhaps in the
greater number of living beings the parts which must be considered as
relative, useful, or necessary, are fewer than those which are
indifferent, useless, and superabundant. But we--ever on the look out to
refer all parts to a certain end--when we can see no apparent use for
them suppose them to have hidden uses, and imagine connections which are
without foundation, and serve only to obscure our perception of Nature
as she really is: we fail to see that we thus rob philosophy of her true
character, which is to inquire into the 'how' of things--into the manner
in which Nature acts--and that we substitute for this true object a vain
idea, seeking to divine the 'why'--the ends which she has proposed in
acting."[85]

_The Dog--Varieties in consequence of Man's Selection._

"Of all animals the dog is most susceptible of impressions, and becomes
most easily modified by moral causes. He is also the one whose nature
is most subject to the variations and alterations caused by physical
influences: he varies to a prodigious extent, in temperament, mental
powers, and in habits: his very form is not constant;" ... but presents
so many differences that "dogs have nothing in common but conformity of
interior organization, and the power of interbreeding freely."...

... "How then can we detect the characters of the original race? How
recognize the effects produced by climate, food, &c.? How, again,
distinguish these from those other effects which come from the
intermixture of races, either when wild or in a state of domestication?
All these causes, in the course of time, alter even the most constant
forms, so that the imprint of Nature does not preserve its sharpness in
races which man has dealt with largely. Those animals which are free to
choose climate and food for themselves can best conserve their original
character, ... but those which man has subjected to his own
influence--which he has taken with him from clime to clime, whose food,
habits, and manner of life he has altered--must also have changed their
form far more than others; and as a matter of fact we find much greater
variety in the species of domesticated anim