What would dog mental reflection even look like? "I should have chosen a different route when chasing that rabbit?"
I don't think there is any evidence for mental reflection at this moment, but the nature of reflection is that is entirely internal, and we don't really know in what manner dogs have cognition.
But, the trend seems to be that we only learn more about the inner lives of animals as time goes on. 100 years ago it was accepted that non-human animals were essentially automatons that didn't feel feelings or have emotions, or engage in any kind of thought, which we know now is not true.
> "I acted in a way that displeased my owner, next time I will not act that way"
This kind of conditioning can take place without any mental reflection--we know this because humans can be conditioned this way without even being consciously aware of it.
This is not to say that the dog is unaware of having displeased their owner (which, as another poster pointed out, is in itself a form of mental reflection, although, as I responded, a very rudimentary one). It's just to say that the dog can be conditioned by this experience to not act that way next time, without being aware of it and without doing any mental reflection.
Anecdote but my dog dreams a lot and sometimes mimics the sounds and motions she makes when we play together. Other times mimics chasing things. Seems like reliving her favorite activities. Might not be intentional but its a form of reflection.
> When I walk into a room containing my dog and the poo it did on the carpet two hours earlier, it is sorry about what it did.
This shows that the dog knows it did something you didn't want it to do, yes. I'm not sure it shows "thinking about ourselves, scrutinising and evaluating what we do and why we do it", which is how the article this discussion is about described "mental reflection". Our dogs have made messes in our house and have shown evidence that they know they're not supposed to, but I see no evidence that they have done any reflection on why they did it.
Of course "mental reflection" is not an all or nothing thing, obviously there is a continuum of possibilities. So a more precise phrasing of my question might be: is there any evidence that dogs can perform mental reflection at a point on that continuum anywhere near the point where humans do it? Or are they only capable of it at a point on the continuum much, much closer to the other end, the "no reflection at all" end?
I'm not sure since we don't have any good way of quantifying "amount of mental reflection". But that doesn't mean there isn't a large difference between dogs and humans in this regard.
