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instinctively. 1859 1860 1861 1866 1869
instinctively. But it would be a serious error to suppose that the greater number of instincts have been acquired by habit in one generation, and then transmitted by inheritance to succeeding generations. 1872

But it would be 1859 1860 1861 1866 1869
It can be clearly shown that 1872

serious error to suppose that the greater number of instincts 1859 1860 1861 1866 1869
wonderful instincts with which we are acquainted, namely, those of the hive-bee and of many ants, could not possibly 1872

acquired. 1859 1860 1861
acquired by habit. 1866 1869

of quite 1859 1860 1861 1866 1869
in many cases of 1872

If we suppose any habitual action to become inherited— and
I think
I think
it can be shown that this does sometimes happen— then the resemblance between what originally was a habit and an instinct becomes so close as not to be distinguished. If Mozart, instead of playing the pianoforte at three years old with wonderfully little practice, had played a tune with no practice at all, he might truly be said to have done so instinctively. But it would be
a
the most
serious error to suppose that the greater number of instincts have been acquired by
habit.
habit
in
in
one
one
generation,
generation,
and
and
then
then
transmitted
transmitted
by
by
inheritance
inheritance
to
to
succeeding
succeeding
generations.
generations.
It can be clearly shown that the most wonderful instincts with which we are
acquainted
acquainted,
namely, those of the hive-bee and of many ants, could not possibly have been
thus
thus
acquired.
It will be universally admitted that instincts are as important as corporeal
structures
structure
for the welfare of each species, under its present conditions of life. Under changed conditions of life, it is at least possible that slight modifications of instinct might be profitable to a species; and if it can be shown that instincts do vary ever so little, then I can see no difficulty in natural selection preserving and continually accumulating variations of instinct to any extent that
was
may be
profitable. It is thus, as I believe, that all the most complex and wonderful instincts have originated. As modifications of corporeal structure arise from, and are increased by, use or habit, and are diminished or lost by disuse, so I do not doubt it has been with instincts. But I believe that the effects of habit are of quite subordinate importance to the effects of the natural selection of what may be called
spontaneous
accidental
variations of instincts;— that is of variations produced by the same unknown causes which produce slight deviations of bodily structure.
No complex instinct can possibly be produced through