For the purposes of our consideration, let us divide the emotions into five general classes, as follows: (1) Instinctive emotions, (2) social emotions, (3) religious emotions, (4) æsthetic emotions, (5) intellectual emotions. We shall now consider each of the above five classes in turn. THE INSTINCTIVE EMOTIONS. Instinct is defined as "unconscious, involuntary, or unreasoning prompting to any action," or "the natural unreasoning impulse by which an animal is guided to the performance of any action, without thought of improving the method." An authority says: "Instinct is a natural impulse leading animals, even prior to all experience, to perform certain actions tending to the welfare of the individual or the perpetuation of the species, apparently without understanding the object at which they may be supposed to aim, or deliberating as to the best methods to employ. In many cases, as in the construction of the cells of the bee, there is a perfection about the result which reasoning man could not have equaled, except by an application of the higher mathematics to direct the operations carried out. Mr. Darwin considers that animals, in time past as now, have varied in their mental qualities, and that those variations are inherited. Instincts also vary slightly in a state of nature. This being so, natural selection can ultimately bring them to a high degree of perfection." It was formerly the fashion to ascribe instinct in the lower animals, and in man, to something akin to "innate ideas" implanted in each species and thereafter continued by inheritance. But the application of the idea of evolution to the science of psychology has resulted in brushing away these old ideas. To-day it holds that that which we call "instinct" is the result of gradual development in the course of evolution, the accumulated experience of the race being stored away in the race memory, each individual adding a little thereto by his acquired habits and experiences. Psychologists now hold that the lower forms of these race tendencies are closely akin to purely reflex actions, and the higher forms, which are known as "instinctive emotions," are phenomena of the subconscious mind resulting from race memory and race experience. Clodd says: "Instinct is the higher form of reflex action. The salmon migrates from sea to river; the bird makes its nest or migrates from one zone to another by an unvarying route, even leaving its young behind to perish; the bee builds its six-sided cell; the spider spins its web; the chick breaks its way through the shell, balances itself, and picks up grains of corn; the newborn babe sucks its mother's breast--all in virtue of like acts on the part of their ancestors, which, arising in the needs of the creature, and gradually becoming automatic, have not varied during long ages, the tendency to repeat them being transmitted within the germ from which insect, fish, bird, and man have severally sprung."