Most people assume that cats are night creatures, and certainly their amazing eyes make them suited for night activity. But the fact is, although your cat might be active at night, he is not active all night, and in the middle of the night he is as likely to be asleep as you are.
No matter how domesticated your cat is, he retains hunter genes, which tell the cat that the best hunting time is around dusk and dawn. Cats are crepuscular—most active at twilight—and least active in the middle of either day or night.