It is a quality observable in human nature, and which we shall endeavour to explain afterwards, that every thing, which is often presented and to which we have been long accustomed, loses its value in our eyes, and is in a little time despised and neglected.

We likewise judge of objects more from comparison than from their real and intrinsic merit; and where we cannot by some contrast enhance their value, we are apt to overlook even what is essentially good in them.

These qualities of the mind have an effect upon joy as well as pride; and it is remarkable, that goods which are common to all mankind, and have become familiar to us by custom, give us little satisfaction; though perhaps of a more excellent kind, than those on which, for their singularity, we set a much higher value.

But though this circumstance operates on both these passions, it has a much greater influence on vanity.

We are rejoiced for many goods, which, on account of their frequency, give us no pride.