In this respect the control exerted by the accepted standard of living is chiefly of a negative character; it acts almost solely to prevent recession from a scale of conspicuous expenditure that has once become habitual. A standard of living is of the nature of habit. It is an habitual scale and method of responding to given stimuli. The difficulty in the way of receding from an accustomed standard is the difficulty of breaking a habit that has once been formed. The relative facility with which an advance in the standard is made means that the life process is a process of unfolding activity and that it will readily unfold in a new direction whenever and wherever the resistance to self-expression decreases. But when the habit of expression along such a given line of low resistance has once been formed, the discharge will seek the accustomed outlet even after a change has taken place in the environment whereby the external resistance has appreciably risen. That heightened facility of expression in a given direction which is called habit may offset a considerable increase in the resistance offered by external circumstances to the unfolding of life in the given direction. As between the various habits, or habitual modes and directions of expression, which go to make up an individual's standard of living, there is an appreciable difference in point of persistence under counteracting circumstances and in point of the degree of imperativeness with which the discharge seeks a given direction.