What is casual and inconstant gives but little joy, and less pride.

We are not much satisfyed with the thing itself; and are still less apt to feel any new degrees of self-satisfaction upon its account.
We foresee and anticipate its change by the imagination; which makes us little satisfyed with the thing: We compare it to ourselves, whose existence is more durable; by which means its inconstancy appears still greater.

It seems ridiculous to infer an excellency in ourselves from an object, which is of so much shorter duration, and attends us during so small a part of our existence.

It will be easy to comprehend the reason, why this cause operates not with the same force in joy as in pride; since the idea of self is not so essential to the former passion as to the latter.
V.I may add as a fifth limitation, or rather enlargement of this system, that general rules have a great influence upon pride and humility, as well as on all the other passions.

Hence we form a notion of different ranks of men, suitable to the power of riches they are possest of; and this notion we change not upon account of any peculiarities of the health or temper of the persons, which may deprive them of all enjoyment in their possessions.