Love your cat? It's because you want a baby.

"The soul, once stirred and set in motion, is lost in itself unless we give it something to grasp; and we must always give it an object to aim at and act on. Plutarch says of those who grow fond of monkeys and little dogs that the loving part that is in us, lacking a legitimate object, rather than remain idle, thus forges itself a false and frivolous one. And we see that the soul in its passions will sooner deceive itself by setting up a false and fantastical object, even contrary to its own belief, than not act against something."

-- Michel de Montaige, Essais, Book I [trans., Donald Frame]