the former. If one object be the cause of another, the second object is
effect to its cause. It is the same case with contiguity: And therefore
the relation being always reciprocal, it may be thought, that the return
of the imagination from the second to the first must also, in every
case, be equally natural as its passage from the first to the second.
But upon farther examination we shall easily discover our mistake.
For supposing the second object, beside its reciprocal relation to the
first, to have also a strong relation to a third object; in that case
the thought, passing from the first object to the second, returns not
back with the same facility, though the relation continues the same; but
is readily carryed on to the third object, by means of the new relation,
which presents itself, and gives a new impulse to the imagination. This
new relation, therefore, weakens the tie betwixt the first and second
objects. The fancy is by its very nature wavering and inconstant; and
considers always two objects as more strongly related together, where it
finds the passage equally easy both in going and returning, than where
the transition is easy only in one of these motions. The double motion
is a kind of a double tie, and binds the objects together in the closest
and most intimate manner.

The second marriage of a mother breaks not the relation of child and
parent; and that relation suffices to convey my imagination from myself
to her with the greatest ease and facility. But after the imagination is
arrived at this point of view, it finds its object to be surrounded with
so many other relations, which challenge its regard, that it knows not
which to prefer, and is at a loss what new object to pitch upon. The
ties of interest and duty bind her to another family, and prevent that
return of the fancy from her to myself, which is necessary to support
the union. The thought has no longer the vibration, requisite to set it
perfectly at ease, and indulge its inclination to change. It goes with
facility, but returns with difficulty; and by that interruption finds
the relation much weakened from what it would be were the passage open
and easy on both sides.

Now to give a reason, why this effect follows not in the same degree
upon the second marriage of a father: we may reflect on what has been
proved already, that though the imagination goes easily from the view of
a lesser object to that of a greater, yet it returns not with the s