Stephen Messenger provides a lesson:
[B]y the 8th century BC in ancient Greece, animals with names began to be recorded in literature. The most famous example perhaps is Odysseus’ faithful hound Argos, whose name means “swift foot,” in Homer’s Odyssey. Other classical texts reveal names of horses, bulls, cows, and even elephants owned by hellenistic kings. In Ancient Rome, personal names for animals abound, given to trusty dogs, horses, and others, and were often chosen from mythology — suggesting that by then animals held a lofty place in the lives of their owners. These non-humans were no longer just animals. Indeed, they were our friends.
Frank Abbott, in his book Society & Politics in Ancient Rome, writes of ancient epitaphs found written in honor of pets. One dog, named Patricus, received this tribute from his grieving owner, revealing a rare early sentiment of love for an animal:
“My eyes were wet with tears, our little dog, when I bore thee (to the grave)… So, Patricus, never again shall thou give me a thousand kisses. Never canst thou be contentedly in my lap. In sadness have I buried thee, and thou deservist. In a resting place of marble, I have put thee for all time by the side of my shade. In thy qualities, sagacious thou wert like a human being. Ah, me! What a loved companion have we lost!”
(“Dogs of NYC” map by WNYC)