seek new ends, and of
course often fail.

Every man has his own measure of reason, be it more or less. It is
largely personal and original with him, and frequent failure is the
penalty he pays for this gift.

But the individual beaver has only the inherited intelligence of his
kind, with such slight addition as his experience may have given him.
He learns to avoid traps, but he does not learn to improve upon his
dam or lodge building, because he does not need to; they answer his
purpose. If he had new and growing wants and aspirations like man,
why, then he would no longer be a beaver. He reacts to outward
conditions, where man reflects and takes thought of things. His
reason, if we prefer to call it such, is practically inerrant. It is
blind, inasmuch as it is unconscious, but it is sure, inasmuch as it
is adequate. It is a part of living nature in a sense that man's is
not. If it makes a mistake, it is such a mistake as nature makes when,
for instance, a hen produces an egg within an egg, or an egg without a
yolk, or when more seeds germinate in the soil than can grow into
plants.

A lower animal's intelligence, I say, compared with man's is blind. It
does not grasp the subject perceived as ours does. When instinct
perceives an object, it reacts to it, or not, just as the object is,
or is not, related to its needs of one kind or another. In many ways
an animal is like a child. What comes first in the child is simple
perception and memory and association of memories, and these make up
the main sum of an animal's intelligence. The child goes on developing
till it reaches the power of reflection and of generalization--a stage
of mentality that the animal never attains to.

All animal life is specialized; each animal is an expert in its own
line of work--the work of its tribe. Beavers do the work of beavers,
they cut down trees and build dams, and all beavers do it alike and
with the same degree of untaught skill. This is instinct, or
unthinking nature.

Of a hot day a dog will often dig down to fresh earth to get cooler
soil to lie on. Or he will go and lie in the creek. All dogs do these
things. Now if the dog were seen to carry stones and sods to dam up
the creek to make a deeper pool to lie in, then he would in a measure
be imitating the beavers, and this, in the dog, could fairly be called
an act of reason, because it is not a necessity of the conditions of
his life; it would be of the nature of an afterthough