A dog naturally loves a man above his own species, and very commonly meets with a return of affection.
As animals are but little susceptible either of the pleasures or pains of the imagination, they can judge of objects only by the sensible good or evil, which they produce, and from that must regulate their affections towards them.

Accordingly we find, that by benefits or injuries we produce their love or hatred; and that by feeding and cherishing any animal, we quickly acquire his affections; as by beating and abusing him we never fail to draw on us his enmity and ill-will.
Love in beasts is not caused so much by relation, as in our species; and that because their thoughts are not so active as to trace relations, except in very obvious instances.

Yet it is easy to remark, that on some occasions it has a considerable influence upon them.

Thus acquaintance, which has the same effect as relation, always produces love in animals either to men or to each other.

For the same reason any likeness among them is the source of affection.