Although instinct and reason appear to be closely allied, they are easily separated and defined.

Instinct is the faculty with which Nature has endowed all animals for the preservation and continuation of their own species. This is accordingly exhibited in various features, as circumstances may call forth the operation of the power; but so wonderful are the attributes of Nature that the details of her arrangements throughout the animal and insect creation give to every class an amount of sense which in many instances surmounts the narrow bounds of simple instinct.

The great characteristic of sheer instinct is its want of progression; it never increases, never improves. It is possessed now in the nineteenth century by every race of living creatures in no larger proportion than was bestowed upon them at the creation.

In general, knowledge increases like a rolling snowball; a certain amount forms a base for extra improvement, and upon successive foundations of increasing altitude the eminence has been attained of the present era. This is the effect of "reason;" but "instinct," although beautiful in its original construction, remains, like the blossom of a tree, ever the same - a limited effect produced by a given cause; an unchangeable law of Nature that certain living beings shall perform certain functions which require a certain amount of intelligence; this amount is supplied by Nature for the performance of the duties required; this is instinct.

Thus, according to the requirements necessitated by the habits of certain living creatures to an equivalent amount is their share of instinct. Reason differs from instinct as combining the effects of thought and reflection; this being a proof of consideration, while instinct is simply a direct emanation from the brain, confined to an impulse.

In our observations of Nature, especially in tropical countries, we see numberless exemplifications of these powers, in some of which the efforts of common instinct halt upon the extreme boundary and have almost a tinge of reason.

What can be more curious than the nest of the tailor-bird - a selection of tough leaves neatly sewn one over the other to form a waterproof exterior to the comfortable little dwelling within? Where does the needle and thread come from? The first is the delicate bill of the bird itself, and the latter is the strong fibre of the bark of a tree, with which the bird sews every leaf, lapping one over the other in the same manner that slates are laid upon a roof.

Nevertheless this is simple instinct; the tailor-bird in the days of Adam constructed her nest in a similar manner, which will be continued without improvement till the end of time.

(Editor：nature)