I felt Mother's fear ripple across her back. (1.20)
Dogs can sense emotions in a way that people can't; we see that early on with our narrator feeling his mother's fear. Dogs don't talk to each other the way people do, but they do communicate through their bodies.
The tastes were exotic and the smells were wonderful, but Mother's anxiety affected all of us, and we ate quickly, savoring nothing. (1.27)
The feelings of other beings greatly affect the dog. If his mother is anxious, he is, too. But this phenomenon can be positive, too. If his human expresses love toward the dog, then the dog feels that as well, and it's a better feeling that he's ever experienced.
Her sadness washed into me, and I pulled against the noose, wanting to go comfort her. (4.57)
Even when the dog is in danger, he can feel the intensity of human emotions. Humans call out to him, almost psychically, and he feels impelled to help them. It's his purpose, after all, right?
"No!" Mom or Ethan would shout when I wet the floor. "Good boy!" they'd sing when I peed in the grass. "Okay, that's good," they'd say when I urinated on the papers. I could not understand what in the world was wrong with them. (6.60)
This is a comic sequence about the frustration people experience when they try to housebreak their pets. Here, it's shown as being pretty darn confusing from the dog's perspective.
One of my favorite things to do was to learn new tricks, as the boy called them, which consisted of him speaking to me in encouraging tones and then feeding me treats. (7.1)
It seems that it isn't necessarily the words that matter, but how they are said. The dog responds well to the encouraging tones. Hey, you get more tricks with honey than you do with vinegar, right?
"Stay"? "Dog Door"? "Good dog"? How were these terms, which I'd heard so often, even remotely related, and which one was "Stay" again? None of this made any sense to me. (7.11-7.12)
The words are very confusing to the dog. Here, the humans are speaking to him in a neutral way, so he is even more confused. Subtlety is lost on the canine kind.
I was astounded at this false accusation. Bad? I'd been accidentally locked in the garage but was more than willing to forgive them. Why where they scowling at me like that, shaking their fingers at me? (7.23)
How does Bailey understand "bad" when he has trouble understanding other terms? Is it the humans' tone and body language that makes the meaning of the word clear? Probably. Nobody says things like "bad dog" in a sweet, loving way.
A mournful sadness drifted off of him, coupled with a gloomy anger that flared sometimes when all he was doing was sitting there looking out the window. (16.14)
Everyone knows that Ethan is sad after the arson incident, but only Bailey the dog senses the true depth of Ethan's despair. Does language sometimes get in the way for people? Sometimes it seems like humans are so used to communicating with language that they've lost the ability to really sense or intuit each other's real feelings.
"I could feel sadness at the edges of her feelings and wondered what it was all about. Perhaps she was bored all day, too." (26.38)
What makes Wendi's sadness different from Senora's? If you'll recall, the dog wanted to comfort Senora even as he was being taken away to be killed. But here, he feels no such compulsion to make Wendi happy. Why not?
"Well, where do you live, huh, boy?" Hannah's hands fumbled for my collar, so I sat. (31.31)
Without being able to speak English, the dog is limited in his ability to be a matchmaker. He can't write a note or bark out words to Hannah to let her know that Ethan likes her. But he can pretend to be lost and get her to look at his collar, which is all the information she needs to give Ethan a call.