The notion of change implies the notion of temporal sequence. A rigid, eternally immutable universe would be out of time, but it would be dead. The concepts of change and of time are inseparably linked together. Action aims at change and is therefore in the temporal order. Human reason is even incapable of conceiving the ideas of timeless existence and of timeless action.

He who acts distinguishes between the time before the action, the time absorbed by the action, and the time after the action has been finished. He cannot be neutral with regard to the lapse of time.

It is acting that provides man with the notion of time and makes him aware of the flux of time. The idea of time is a praxeological category.

Man is subject to the passing of time. He comes into existence, grows, becomes old, and passes away. His time is scarce. He must economize it as he economizes other scarce factors.

The economization of time has a peculiar character because of the uniqueness and irreversibility of the temporal order. The importance of these facts manifests itself in every part of the theory of action.

Two actions of an individual are never synchronous; their temporal relation is that of sooner and later. Actions of various individuals can be considered as synchronous only in the light of the physical methods for the measurement of time.

A very common criticism of the libertarian position runs as follows: Of course we do not like violence, and libertarians perform a useful service in stressing its dangers. But you are very simpliste because you ignore the other significant forms of coercion exercised in society—private coercive power, apart from the violence wielded by the State or the criminal. The government should stand ready to employ its coercion to check or offset this private coercion.

It is quite common and even fashionable to discuss market phenomena in terms of “power”—that is, in terms appropriate only to the battlefield. We have seen the fallacy of the “back-to-the-jungle” criticism of the market and we have seen how the fallacious “economic-power” concept has been applied to the exchange economy.

The result sought by an action is called its end, goal, or aim. One uses these terms in ordinary speech also to signify intermediate ends, goals, or aims; these are points which acting man wants to attain only because he believes that he will reach his ultimate end, goal or aim in passing beyond them. Strictly speaking the end, goal, or aim of any action is always the relief from a felt uneasiness.

Acting man chooses between various opportunities offered for choice. He prefers one alternative to others.

Notwithstanding all declarations to the contrary, the immense majority of men aim first of all at an improvement of the material conditions of well-being. They want more and better food, better homes and clothes, and a thousand other amenities. They strive after abundance and health. Taking these goals as given, applied physiology tries to determine what means are best suited to provide as much satisfaction as possible. It distinguishes, from this point of view, between man’s “real” needs and imaginary and spurious appetites.