The effects of resemblance are not so remarkable; but as that relation makes a considerable ingredient in causation, of which all animals shew so evident a judgment, we may conclude that the three relations of resemblance, contiguity and causation operate in the same manner upon beasts as upon human creatures.
There are also instances of the relation of impressions, sufficient to convince us, that there is an union of certain affections with each other in the inferior species of creatures as well as in the superior, and that their minds are frequently conveyed through a series of connected emotions.

A dog, when elevated with joy, runs naturally into love and kindness, whether of his master or of the sex.

In like manner, when full of pain and sorrow, he becomes quarrelsome and illnatured; and that passion; which at first was grief, is by the smallest occasion converted into anger.
Thus all the internal principles, that are necessary in us to produce either pride or humility, are commcm to all creaturn; and since the causes, which excite these passions, are likewise the same, we may justly conclude, that these causes operate after the same manner through the whole animal creation.

My hypothesis Is so simple, and supposes so little reflection and judgment, that it is applicable to every sensible creature; which must not only be allowed to be a convincing proof of its veracity, but, I am confident, will be found an objection to every other system..