INSTINCTS APPEAR IN SUCCESSION AS REQUIRED.--It is not well that we should be started on too many different lines of activity at once, hence our instincts do not all appear at the same time. Only as fast as we need additional activities do they ripen. Our very earliest activities are concerned chiefly with feeding, hence we first have the instincts which prompt us to take our food and to cry for it when we are hungry. Also we find useful such abbreviated instincts, called _reflexes_, as sneezing, snuffling, gagging, vomiting, starting, etc.; hence we have the instincts enabling us to do these things. Soon comes the time for teething, and, to help the matter along, the instinct of biting enters, and the rubber ring is in demand. The time approaches when we are to feed ourselves, so the instinct arises to carry everything to the mouth. Now we have grown strong and must assume an erect attitude, hence the instinct to sit up and then to stand. Locomotion comes next, and with it the instinct to creep and walk. Also a language must be learned, and we must take part in the busy life about us and do as other people do; so the instinct to imitate arises that we may learn things quickly and easily. We need a spur to keep us up to our best effort, so the instinct of emulation emerges. We must defend ourselves, so the instinct of pugnacity is born. We need to be cautious, hence the instinct of fear. We need to be investigative, hence the instinct of curiosity. Much self-directed activity is necessary for our development, hence the play instinct. It is best that we should come to know and serve others, so the instincts of sociability and sympathy arise. We need to select a mate and care for offspring, hence the instinct of love for the other sex, and the parental instinct. This is far from a complete list of our instincts, and I have not tried to follow the order of their development, but I have given enough to show the origin of many of our life's most important activities.