Instinct and Reason
Instinct is, properly, the innate and inherited impulse which drives animals to do certain things which seem to be quite rational, without any conscious design. More precisely, “it is a natural spontaneous propensity or impulse, in the lower animals or in men, moving them without reasoning towards actions essential to their existence, preservation, or development; as, the instinct of self-preservation.”
Take a few examples of instinct. Bees make six sided cells for storing their honey. They always make them the same size and the same shape (mathematically perfect hexagons). Yet they never learn to make them; for the young worker-bees, as soon as they are born, set to work making these cells as perfectly as the old experienced bees. Apparently, they have no conscious purpose in doing this; they do it blindly, yet perfectly.
In the same way, young birds have never seen a nest built, and have had no lessons in the art of nest building; yet when the nesting time comes round, they know exactly how to do it. And a bird of one species will never make the mistake of building the kind of nest characteristic of another species. Sparrows never make nests as swallows do, nor swallows like those of others.
We cannot explain these actions of insects and birds. As they are done apparently without reasoning of conscious design, but are due to some blind inner impulse; we say they are due to “instinct”. But we can sum up the characteristics of instinct, which are these: (a) instinct is adaptive, that is, directed to some end ; (b) that end is somehow connected with the welfare of the species or the individual ; (c) the reaction is psychologically complex ; (d) it is native or inherited, and not learned.
By reason we mean the power of drawing certain logical conclusions from given premises: the power of thinking, of choosing to do certain things because we consider them wise or advantageous, and of doing things with a conscious end in view. For example, men do not build houses as birds build nests. They have a clear idea in their minds what kind of house they want, and of what materials they wish to make it. The architect, after much thought, draws a plan ; and the builders calculate how many bricks and how much mortar will be needed. At every step, there is deliberate thought and conscious design and choice. So reason is quite different from instinct. It is commonly. said that animals act from instinct and men from reason. But some higher animals, such as dogs, horses and elephants, have a certain amount of reason, and we call them intelligent; and there is a lot of instinct in men. On the whole, however, reason is characteristic of men, and instinct of animals, birds, fishes and insects.
