You spy with your little eye, dogs can adopt the perspective of humans
Humans are able to interpret the behavior of others by attributing mental states to them (And to themselves). By adopting the perspectives of other persons, they can assume their emotions, needs and intentions and react accordingly. In the animal kingdom, the ability to attribute mental states (Theory of Mind) is a highly contentious issue. Cognitive biologists could demonstrate with a new test procedure that dogs are not only able to identify whether a human has an eye on a food source and, therefore, knows where the food has been hidden. They can also apply this knowledge in order to correctly interpret cues by humans and find food they cannot see themselves. Ref. Source 8x.
Dogs know when they don't know. Researchers have shown that dogs possess some 'metacognitive' abilities -- specifically, they are aware of when they do not have enough information to solve a problem and will actively seek more information. The researchers created a test in which dogs had to find a reward behind one of two fences. They found that the dogs looked for additional information significantly more often when they had not seen where the reward was hidden. Source 8e.
Good dog? Bad dog? Their personalities can change. When dog-parents spend extra time scratching their dogs' bellies, take their dogs out for long walks and games of fetch, or even when they feel constant frustration over their dogs' naughty chewing habits, they are gradually shaping their dogs' personalities. Source 5t.