I often describe a dog's mental capacity of that of a 2-3-year-old human. I do this to help people understand that in training, they can only handle so much before being overwhelmed. However, the dogs psychological capacity is so much more.
Dogs have an innate ability to call us out on our crap. According to a recent study led by Akiko Takoka of Kyko University in Japan, dogs can tell when humans are unreliable or dishonest. They will obey a certain series of cues as long as the person is consistent with and honest with what they are asking. This in short means a dog will not trust a human who is not trust worthy. This is why it is so important to mean what you say and to make sure you always have the animals best interest at heart. They are not blind or dumb creatures and are able to read peoples intent. Dogs can literally sense a change in humans behavior when we are being deceptive.
Have you ever noticed that certain dogs can "behave" perfectly for one person and not the other? This is because they have learned to trust the one who has taken the time to earn that commitment. For example, my dog has been described as very stubborn. I used to be confused when people who watched him pointed that out because it is not the case when I ask a cue from him. This is because we were able to form a bond when he was young. If I ask him to Come he is able to trust that I am not going to grab his collar and make him do something unpleasant. Over time the recall cue has been used to keep him out of harm's way or to offer him a reward. He knows I am not trying to be sneaky or mislead and him because I have shown him that I am a consistent and fair leader.
Humans like to label their canine companions as "dumb" or unable to learn because their dog seems to ignore a known cue. This is not the case. Even though dogs are primarily bred for human companionship does not mean that they will trust your direction in every situation. They still have the instinct of self-preservation and if their human is an inconsistent leader, they will offer the same behavior.
Dogs are complex and remarkable creatures that often do not receive the credit due to them. For an animal that can perceive slight changes in a person's emotion and smell out hidden diseases, it is quite amazing that they are willing to listen to people at all.
As research continues, we are discovering more and more about our canines mental capacity. The more we slow down and earn our best friends trust, the more they will be willing to trust our discernment.