Enzo pauses the narrative to lament his lack of thumbs, beginning by saying that monkeys, practically the dumbest species on earth, have thumbs. The duck-billed platypus is the stupidest, but only marginally more so than a monkey. The thumbs of the monkeys were meant for dogs. Enzo says, "give me my thumbs, you fucking monkeys!" and then, as an aside, says he loves the Al Pacino remake of Scarface, although it is incomparable to the excellent Godfather movies.
Again, one of the primary ways that Enzo sees humans as different from dogs is a physical trait: thumbs. He also, following his hierarchy of dog breeds, begins to set up a hierarchy of animal species. His aside about the movies will be a recurring motif throughout the novel. TV informs how he sees the world, and he uses movie references to make his points.
Enzo says he watches too much TV. Denny turns it on in the morning when he leaves, and warns Enzo not to watch all day, but he does anyway. Fortunately, Denny lets Enzo watch a lot of Speed Channel and NASCAR because racing is Enzo's favorite, but Denny also insists on leaving other channels on for variety. When he's watching other channels like PBS or the Discovery Channel, Enzo learns about other cultures and ways of life, which leads him to think about his own life and what makes sense and what doesn't.
Enzo will later refer to TV as his "education," and we learn here what he's learned from all his viewing. Television gives Enzo a way to not just engage with racing, but also provides him with material and a starting point to consider more spiritual and theoretical questions.
Many shows discuss Darwin at length. The educational shows Enzo's watched on evolution are very well thought out and researched in Enzo's opinion, although he doesn't understand why evolution and creation can't coexist. Enzo sees spiritualism and science as one, the marriage of bodies and spirits in one human package. Instead, scientific theorists go on at length about how monkeys are the most closely related species to humans. Enzo believes this is speculation. Enzo says the most important idea isn't whether humans came from monkeys or fish, it's that when the body became human enough, a human soul slipped in.
This is one place where it’s made more obvious that Enzo, as a dog, doesn't grasp things as humans do. His beliefs here are possibly due to his dislike of monkeys and his envy of their thumbs. However, also note the dissonance at play here—Enzo will later say that he wants to be human so he can partake in intellectual pursuits, but here he diminishes the intellectual pursuits of those who are already human.
Enzo's theory is that primates are not the closest relatives to humans, as those on TV believe, but dogs are. His first case-in-point is a dog’s dew claw, which he believes is evidence of a pre-emergent thumb. Enzo believes, further, that men have bred the thumb out of certain dog breeds through selective breeding in an attempt to prevent dogs from evolving into dexterous and dangerous mammals.
Enzo thinks very highly of himself and dogs in general. Once again, he sees humans' physical traits as the reason for their dominance, rather than any of their intellectual advantages.
Enzo believes that the domestication of dogs is motivated by the fear that if left to evolve on their own, dogs would develop thumbs and smaller tongues and would then be superior to men. This is the reason why dogs must live under constant human supervision. Enzo believes that this plan was hatched in a back room of the White House by an evil adviser and a president lacking in morality and intellect. Enzo believes they made the correct assessment that dogs are all progressive on social issues, although this assessment comes from paranoia rather than spiritual insight.
Further, Enzo sees that dogs have the potential to surpass humans if they were allowed to develop key physical traits. Notice also how Enzo interprets hearing about politics from Denny. We can't know exactly what he heard, but whatever it was manifests in a distrust of government because of what Enzo believes their position on dogs is.
Enzo's second case-in-point is the werewolf. When the man steps out of the forest on the full moon, he doesn't find himself transformed into a monkey.
Enzo sees the combination of man and dog as proof that they're nearly equivalent in the evolutionary hierarchy.