This idea is presently converted into an impression, and acquires such a degree of force and vivacity, as to become the very passion itself, and produce an equal emotion, as any original affection.

However instantaneous this change of the idea into an impression may be, it proceeds from certain views and reflections, which will not escape the strict scrutiny of a.
philosopher, though they may the person himself, who makes them.
It is evident, that the idea, or rather impression of ourselves is always intimately present with us, and that our consciousness gives us so lively a conception of our own person, that it is not possible to imagine, that any thing can in this particular go beyond it.

Whatever object, therefore, is related to ourselves must be conceived with a little vivacity of conception, according to the foregoing principles; and though this relation should not be so strong as that of causation, it must still have a considerable influence.

Resemblance and contiguity are relations not to be neglected; especially when by an inference from cause and effect, and by the observation of external signs, we are informed of the real existence of the object, which is resembling or contiguous.
Now it is obvious, that nature has preserved a great resemblance among all human creatures, and that we never remark any passion or principle in others, of which, in some degree or other, we may not find a parallel in ourselves.

The case is the same with the fabric of the mind, as with that of the body.