Contrasting with the simple scheme of animals whose movement of like and dislike are only in relation to the present, Hobbes justifies the complexity of the human character by pointing out the property of memory and imagination. Through those psychic agencies, we are capable of postponing the pleasure for greater fulfillment instead of reaction instantly toward it. Hence, human beings are capable of desiring what is not present except in imagination. Because imagination is a restless agency, human appetites are unlimited and insatiable. Some of the strongest natural desires are the craving for power and domination over others, and the ambition for recognition and precedence. The counterpart of this passion for pride is fear. In animals, fear may be understood as merely being affrighted, while in human creature, Hobbes describes it as the dread of falling behind others, anxiety ultimately deriving from the fear of death. Human life is then a perpetual tension between pride and fear, and every man is the enemy of every man, each one engaged in a competition or supremacy in which he is always preoccupied about failure.
Reason, the counterpart of appetite, is characterized by the ability of regulating one's own "train of thought," not only to perceive the cause of hat has been imagined, but to seek the effects that can be produced by it. Secondly, Hobbes points out the power o speech which is the ground of mutual understanding and of agreement between individuals pursuing their desires. Thus, on account of their power of speech and imagination, human beings are contract-making creature, the latter mean being artificial, yet necessary to change the natural condition of suspicion and antagonism between them. However, reason warns us against entering such covenant without precaution. Therefore, reason is insufficient to resolve the tension between pride and fear. Hobbes also assumes that reason itself has a cause which is fear. The latter is an active and imaginative agency of the human character, and provokes in individuals the impulse of elaborating measures against the object of fear. Yet, because one cannot live under the condition of permanent preparedness against external evil, one need to agree with others for the settlement of a condition of peace allowing the release of the tension and consequently the possible fulfillment of appetite. Peace is the result of the social contract stating that death is th common enemy. And in order to achieve this state, people need the constant presence of a sovereign authority securing covenants from corruption. Therefore, the social contract is a natural endeavor deriving from the fear of not fulfilling one's own appetite for pride.
