Ok, now I'm showing my really dorky, scientific side. To test to see if an animal is sentient (aware of it's existence) they actually do a test to see if they can identify themselves in a mirror. I'm not totally sure how the test works, but the do it on monkeys and dolphins, which are the only animals that know that it is them in the mirror. I definately don't think it's a dumb question though. Yorkies are so smart that I sometimes wonder if mine is senitent.
