The Servant Problem

The Servant Problem is a science fiction novella written by Robert F. Young.

After locking the car, he started up the walk, Zarathustra at his heels. He knocked on the front door. Presently he knocked again. The door creaked, swung partially open. He frowned. Had she forgotten to latch it? he wondered. Or had she deliberately left it unlatched so that Zarathustra could get in? Zarathustra himself lent plausibility to the latter conjecture by rising up on his hind legs and pushing the door the rest of the way open with his forepaws, after which he trotted into the hall and disappeared.