We call contentment or satisfaction that state of a human being which does not and cannot result in any action. Acting man is eager to substitute a more satisfactory state of affairs for a less satisfactory. His mind imagines conditions which suit him better, and his action aims at bringing about this desired state. The incentive that impels a man to act is always some uneasiness .
A man perfectly content with the state of his affairs would have no incentive to change things. He would have neither wishes nor desires; he would be perfectly [p. 14] happy. He would not act; he would simply live free from care.
But to make a man act, uneasiness and the image of a more satisfactory state alone are not sufficient. A third condition is required: the expectation that purposeful behavior has the power to remove or at least to alleviate the felt uneasiness. In the absence of this condition no action is feasible. Man must yield to the inevitable. He must submit to destiny.
These are the general conditions of human action. Man is the being that lives under these conditions. He is not only homo sapiens, but no less homo agens. Beings of human descent who either from birth or from acquired defects are unchangeably unfit for any action (in the strict sense of the term and not merely in the legal sense) are practically not human. Although the statutes and biology consider them to be men, they lack the essential feature of humanity. The newborn child too is not an acting being. It has not yet gone the whole way from conception to the full development of its human qualities. But at the end of this evolution it becomes an acting being.
In colloquial speech we call a man "happy" who has succeeded in attaining his ends. A more adequate description of his state would be that he is happier than he was before. There is however no valid objection to a usage that defines human action as the striving for happiness.
But we must avoid current misunderstandings. The ultimate goal of human action is always the satisfaction of the acting man's desire. There is no standard of greater or lesser satisfaction other than individual judgments of value, different for various people and for the same people at various times. What makes a man feel uneasy and less uneasy is established by him from the standard of his own will and judgment, from his personal and subjective valuation. Nobody is in a position to decree what should make a fellow man happier.
To establish this fact does not refer in any way to the antitheses of egoism and altruism, of materialism and idealism, of individualism and collectivism, of atheism and religion. There are people whose only aim is to improve the condition of their own ego. There are other people with whom awareness of the troubles of their fellow men causes as much uneasiness as or even more uneasiness than their own wants. There are people who desire nothing else than the satisfaction of their appetites for sexual intercourse, food, drinks, fine homes, and other material things. But other men care more for the satisfactions commonly called "higher" and "ideal." There are individuals eager to adjust their actions to the requirements of social cooperation; there [p. 15] are, on the other hand, refractory people who defy the rules of social life. There are people for whom the ultimate goal of the earthly pilgrimage is the preparation for a life of bliss. There are other people who do not believe in the teachings of any religion and do not allow their actions to be influenced by them.
Praxeology is indifferent to the ultimate goals of action. Its findings are valid for all kinds of action irrespective of the ends aimed at. It is a science of means, not of ends. It applies the term happiness in a purely formal sense. In the praxeological terminology the proposition: man's unique aim is to attain happiness, is tautological. It does not imply any statement about the state of affairs from which man expects happiness.
The idea that the incentive of human activity is always some uneasiness and its aim always to remove such uneasiness as far as possible, that is, to make the acting men feel happier, is the essence of the teachings of Eudaemonism and Hedonism. Epicurean <arapacia> is that state of perfect happiness and contentment at which all human activity aims without ever wholly attaining it. In the face of the grandeur of this cognition it is of little avail only that many representatives of this philosophy failed to recognize the purely formal character of the notions pain and pleasure and gave them a material and carnal meaning. The theological, mystical, and other schools of a heteronomous ethic did not shake the core of Epicureanism because they could not raise any other objection than its neglect of the "higher" and "nobler" pleasures. It is true that the writings of many earlier champions of Eudaemonism, Hedonism, and Utilitarianism are in some points open to misinterpretation. But the language of modern philosophers and still more that of the modern economists is so precise and straightforward that no misinterpretation can possibly occur.
On Instincts and Impulses
One does not further the comprehension of the fundamental problem of human action by the methods of instinct-sociology. This school classifies the various concrete goals of human action and assigns to each class a special instinct as its motive. Man appears as a being driven by various innate instincts and dispositions. It is assumed that this explanation demolishes once for all the odious teachings of economics and utilitarian ethics. However, Feuerbach has already justly observed that every instinct is an instinct to happiness . The method of instinct-psychology and instinct-sociology consists in an arbitrary classification of the immediate goals of action and in a hypostasis of each. Whereas praxeology says that the goal of an action is to remove [p. 16] a certain uneasiness, instinct-psychology says it is the satisfaction of an instinctive urge.
Many champions of the instinct school are convinced that they have proved that action is not determined by reason, but stems from the profound depths of innate forces, impulses, instincts, and dispositions which are not open to any rational elucidation. They are certain they have succeeded in exposing the shallowness of rationalism and disparage economics as "a tissue of false conclusions drawn from false psychological assumptions."  Yet rationalism, praxeology, and economics do not deal with the ultimate springs and goals of action, but with the means applied for the attainment of an end sought. However unfathomable the depths may be from which an impulse or instinct emerges, the means which man chooses for its satisfaction are determined by a rational consideration of expense and success. 
He who acts under an emotional impulse also acts. What distinguishes an emotional action from other actions is the valuation of input and output. Emotions disarrange valuations. Inflamed with passion, man sees the goal as more desirable and the price he has to pay for it as less burdensome than he would in cool deliberation. Men have never doubted that even in the state of emotion means and ends are pondered and that it is possible to influence the outcome of this deliberation by rendering more costly the yielding to the passionate impulse. To punish criminal offenses committed in a state of emotional excitement or intoxication more mildly than other offenses is tantamount to encouraging such excesses. The threat of severe retaliation does not fail to deter even people driven by seemingly irresistible passion.
We interpret animal behavior on the assumption that the animal yields to the impulse which prevails at the moment. As we observe that the animal feeds, cohabits, and attacks other animals or men, we speak of its instincts of nourishment, of reproduction, and of aggression. We assume that such instincts are innate and peremptorily ask for satisfaction.
But is different with man. Man is not a being who cannot help yielding to the impulse that most urgently asks for satisfaction. Man is a being capable of subduing his instincts, emotions, and impulses; he can rationalize his behavior. He renounces the satisfaction of a burning impulse in order to satisfy other desires. He is not a puppet of his appetites. A man does not ravish every female that stirs his senses; he does not devour every piece of food that entices him; he does not knock down every fellow he would like to kill. He arranges [p. 17] his wishes and desires into a scale, he chooses; in short, he acts. What distinguishes man from beasts is precisely that he adjusts his behavior deliberatively. Man is the being that has inhibitions, that can master his impulses and desires, that has the power to suppress instinctive desires and impulses.
It may happen that an impulse emerges with such vehemence that no disadvantage which its satisfaction may cause appears great enough to prevent the individual from satisfying it. In this case too there is choosing. Man decides in favor of yielding to the desire concerned. 
 Cf. Lock, An Essay Concerning Human Understanding, ed. Fraser
(Oxford, 1894), I, 331-333; Leibniz, Nouveaux essais sur l'entendement humain, ed.
Fammarion, p. 119.
 Cf. Feuerbach, Sämmtliche Werke, ed. Bolin and Jodl (Stuttgart, 1907), X, 231.
 Cf. William McDougall, An Introduction to Social Psychology
(14th ed. Boston, 1921), p. 11.
 Cf. Mises, Epistemological Problems of Economics, trans. by G. Reisman (New York, 1960), pp. 52 ff.
 In such cases a great role is played by the circumstances that the two satisfactions concerned--that expected from
yielding to the impulse and that expected from the avoidance of its undesirable consequences--
are not simultaneous. Cf. below, pp. 479-490.