I had a dog (German Shepherd) who would NOT pee indoors because she'd been gently led to understand that that was wrong. One time I ended up in hospital over night and was unable to get home until about 10:00 AM. She'd been inside for over 14 hours and she had peed. When I got home she was slow to come greet me and when she did her head was down. I saw the puddle and mopped it up and called her over. I gave her a hug and said stuff like, "It's OK", "Alright". She knew she'd done wrong, but stuff happens. I don't know that a moral sense necessarily involves notions of right and wrong (Bill D is better informed to speak to that), but that dog knew the difference. I have numerous examples that demonstrate it, but getting into them here is a no-go.