Page:Treatise of Human Nature (1888).djvu/444

422  passion. For the same reason, despair, tho' contrary to security, has a like influence.

'Tis certain nothing more powerfully animates any affection, than to conceal some part of its object by throwing it into a kind of shade, which at the same time that it shews enough to pre-possess us in favour of the object, leaves still some work for the imagination. Besides that obscurity is always attended with a kind of uncertainty; the effort, which the fancy makes to compleat the idea, rouzes the spirits, and gives an additional force to the passion.

As despair and security, tho' contrary to each other, produce the same effects; so absence is observ'd to have contrary effects, and in different circumstances either encreases or diminishes our affections. The Duc de la Rochefoucault has very well observ'd, that absence destroys weak passions, but encreases strong; as the wind extinguishes a candle, but blows up a fire. Long absence naturally weakens our idea, and diminishes the passion: But where the idea is so strong and lively as to support itself, the uneasiness, arising from absence, encreases the passion, and gives it new force and violence. 

nothing has a greater effect both to encrease and diminish our passions, to convert pleasure into pain, and pain into pleasure, than custom and repetition. Custom has two original effects upon the mind, in bestowing a facility in the performance of any action or the conception of any object; and afterwards a tendency or inclination towards it; and from these we may account for all its other effects, however extraordinary.

When the soul applies itself to the performance of any action, or the conception of any object, to which it is not accustom'd, there is a certain unpliableness in the faculties, 