Contributions to the theory of natural selection. A series of essays ... By Alfred Russel Wallace ...

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VI.
THE PHILOSOPHY OF BIRDS' NESTS.
Inst2inct or Reason in the Construction of Bilrds' N~ests.
BIRDS, we are told, build their nests by instinct, while
man constructs his dwelling by the exercise of reason.
Birds never change, but continue to build for ever on
the self-same plan; man alters and improves his houses
continually. Reason advances; instinct is stationary.
This doctrine is so very general that it may almost
be said to be universally adopted. Men who agree
on nothing else, accept this as a good explanation of
the facts. Philosophers and poets, metaphysicians and
divines, naturalists and the general public, not only
agree in believing this to be probable, but even adopt
it as a sort of axiom that is so self-evident as to need
no proof, and use it as the very foundation of their
speculations on instinct and reason. A belief so general)
one would think, must rest on indisputable facts, and
be a logical deduction from them. Yet I have come to
the conclusion that not only is it very doubtful, but
absolutely erroneous; that it not only deviates widely
from the truth, but is in almost every particular exactly
opposed to it. I believe, in short, that birds do nzot
build their nests by instinct; that man does not conP 2