Every thing good in love belongs to the brutes as well as to man, and even they, as if this sentiment could never be pure, seem to have a small portion of jealousy. Among us, this passion always implies some distrust of ourselves, some distant knowledge of our own weakness, while brutes are never jealous but in proportion to their strength, ardour for, and propensity to pleasure. The reason is, that our jealousy depends on our ideas, and theirs on sentiment. Having once enjoyed, they desire to enjoy again; and feeling their strength, they drive away all that would occupy their place. Their jealousy is without reflection, they turn it not against the object of their love: of their pleasures alone are they jealous. But are animals confined merely to those passions we have described? Are fear, rage, horror, love, and jealousy, the only durable affections they are capable of experiencing? To me it appears that, independent of these passions, which arise from their natural feelings, they have others, which are communicated to them by example, imitation, and habit. They have a kind of friendship, pride, and ambition, and though we may be convinced, that in all their operations there is neither reflection nor thought, yet as all their habits seem to imply some degree of intelligence, and to form the shade between them and man, it requires, in a peculiar manner, our strict examination. Is there any thing exceeds the attachment of the dog to its master? On the grave that contained his dust has this animal been known to breathe its last. But (without quoting prodigies or heroes) with what fidelity does he accompany, follow, and defend his master! With what eagerness does he solicit his caresses! With what docility does he obey him! With what patience does he suffer his bad humours, and his frequently unjust corrections! With what mildness and humility does he endeavour to be restored to favour! What emotion and anxiety does he express when his master is absent! and what joy when he returns!--From all these circumstances it is possible not to distinguish true marks of friendship? Even among the human species it is expressed in characters of superior energy. This friendship is the same as that of a female for her favourite bird, or of a child for its play-thing. Both are equally blind and void of reflection; that of the animal is more natural, since it is founded on necessity, while that of the other is only an insipid amusement, in which the mind in no degree partakes These childish habits subsist merely by idleness, and are more or less strong as the brain is more or less vacant.