I don't know how well you feel that you know our black dog. Let me say a few words to help. He's turning 10 yrs old later this month yet we are routinely asked if he is a puppy. He is ecstatically enthusiastic about almost everything that we do with him.
As an example, I still do rehabilitation exercises with him for his elbow. When he realizes that the exercise routine is about to begin, he jumps up and down, does a few spins, and then barks while tossing his head upward in joy.
He throws himself into most of the exercises as if he hasn't already done about 500 days of exercises since his surgery.
Except when I have a migraine, it is almost impossible not to get happy along with him.
He symbolizes a "Life is Good" attitude.
It is very rare to see him look as serious as in this photo, which is why I like it so much.