*Habit* also involves the suspension of reason and motive in the performance of individual acts; but it differs from passion in that its acts were in the beginning prompted by reason and motive. Indeed, it may be plausibly maintained that in each habitual act there is a virtual remembrance—a recollection too transient to be itself remembered—of the reasoning or motive which induced the first act of the series. In some cases the habitual act is performed, as it is said, unconsciously, certainly with a consciousness so evanescent as to leave no trace of itself. In other cases the act is performed consciously, but as by a felt necessity, in consequence of an uneasy sensation—analogous to hunger and thirst—which can be allayed in this way only. Under this last head we may class, in the first place, habits of criminal indulgence, including the indulgence of morbid and depraved appetite; secondly, many of those morally indifferent habits, which constitute a large portion of a regular and systematic life; and thirdly, habits of virtuous conduct, of industry, of punctuality, of charity. *Habit bears a most momentous part in the formation and growth of character*, whether for evil or for good. It is in the easy and rapid formation of habit that lies the imminent peril of single acts of vicious indulgence. The first act is performed with the determination that it shall be the last of its kind. But of all examples one’s own is that which he is most prone to follow, and of all bad examples one’s own is the most dangerous. The precedent once established, there is the strongest temptation to repeat it, still with a conscious power of self-control, and with the resolution to limit the degree and to arrest the course of indulgence, so as to evade the ultimate disgrace and ruin to which it tends. But before the pre-determined limit is reached, the indulgence has become a habit; its suspension is painful; its continuance or renewal seems essential to comfortable existence; and even in those ultimate stages when its very pleasure has lapsed into satiety, and then into wretchedness, its discontinuance threatens still greater wretchedness, because the craving is even more intense when the enjoyment has ceased.