Dulcia non ferimus: succo renovamur amaro.
Ovid. art. Amand. l. 3.

Insipido è quel dolce, che condito
Non è di qualche amaro, e tosto satia.
Aminta di Tasso.

These violent delights have violent ends,
And in their triumph die. The sweetest honey
Is loathsome in its own deliciousness,
And in the taste confounds the appetite;
Therefore love mod’rately, long love doth so:
Too swift arrives as tardy as too slow.
Romeo and Juliet, act 2. sc. 6.

The same holds in the causes of all violent pleasures: these causes are not naturally susceptible of habit. Great passions suddenly raised are incompatible with a habit of any sort. In particular they never produce affection or aversion. A man who at first sight falls violently in love, has a strong desire of enjoyment, but no affection for the woman[25]. A man who is surprised with an unexpected savour, burns for an opportunity to exert his gratitude, without having any affection for his benefactor. Neither does desire of vengeance for an atrocious injury involve aversion.

It is perhaps not easy to say why moderate pleasures gather strength by custom. But two causes concur to prevent this effect in the more intense pleasures. These, by an original law in our nature, increase quickly to their full growth, and decay with no less precipitation[26]; and custom is too slow in its operation to overcome this law. Another cause is not less powerful. The mind is exhausted with pleasure as well as with pain. Exquisite pleasure is extremely fatiguing; occasioning, as a naturalist would say, great expence of animal spirits[27]. And therefore, of such the mind cannot bear so frequent gratification as to superinduce a habit. If the thing which raises the pleasure return before the mind have recovered its tone and relish, disgust ensues instead of pleasure.

A habit never fails to admonish us of the wonted time of gratification, by raising a pain for want of the object, and a desire to have it. The pain of want is always first felt; the desire naturally follows; and upon presenting the object, both vanish instantaneously. Thus a man accustomed to tobacco, feels, at the end of the usual interval, a confused pain of want, which in its first appearance points at nothing in particular, though it soon settles upon its accustomed object. The same may be observed in persons addicted to drinking, who are often in an uneasy restless state before they think of their bottle. In pleasures indulged regularly and at equal intervals, the appetite, remarkably obsequious to custom, returns regularly with the usual time of gratification; and a sight of the object in the interim, has scarce any power to move it. This pain of want arising from habit, seems directly opposite to that of satiety. Singular it must appear, that frequency of gratification should produce effects so opposite as are the pains of excess and of want.

The appetites that respect the preservation and propagation of our species, are attended with a pain of want similar to that occasioned by habit. Hunger and thirst are uneasy sensations of want, which always precede the desire of eating or drinking: and a pain for want of carnal enjoyment precedes the desire of a proper object. The pain being thus felt independent of an object, cannot be cured but by gratification. An ordinary passion, in which desire precedes the pain of want, is in a different condition. It is never felt but while the object is in view; and therefore by removing the object out of thought, it vanisheth with its desire and pain of want[28].

These natural appetites above mentioned, differ from habit in the following particular, They have an undetermined direction toward all objects of gratification in general; whereas an habitual appetite is directed upon a particular object. The attachment we have by habit to a particular woman, differs widely from the natural passion which comprehends the whole sex; and the habitual relish for a particular dish, is far from being the same with a vague appetite for food. Notwithstanding this difference, it is still remarkable, that nature hath inforced the gratification of certain natural appetites essential to the species, by a pain of the same sort with that which habit produceth.

The pain of habit is less under our power, than any other pain for want of gratification. Hunger and thirst are more easily endured, especially at first, than an unusual intermission of any habitual pleasure. We often hear persons declaring, they would forego sleep or food, rather than snuff or any other habitual trifle. We must not however conclude, that the gratification of an habitual appetite affords the same delight with the gratification of one that is natural. Far from it: the pain of want only is greater.

The slow and reiterated acts that produce a habit, strengthen the mind to enjoy the habitual pleasure in greater quantity and more frequency than originally; and by this means a habit of intemperate gratification is often formed. After unbounded acts of intemperance, the habitual relish is soon restored, and the pain for want of enjoyment returns with fresh vigor.