Why do "dogs look at people lowly"

We can first take a look at the life of wolf packs regarding this question.

Wolves, as social animals with a strong hierarchy, have strict rank differentiation within their groups. The majestic alpha male wolf, once it successfully challenges for its position, it becomes the king. Female wolves are responsible for reproduction and nurturing, while male wolves assist the alpha in hunting. The authority of the alpha is unquestionable; as long as another wolf does not challenge the alpha, no other wolf will compete with it for food or mates. However, conflicts between male wolves often occur.

Dogs are creatures that have evolved (or regressed) from wolves after over ten thousand years of domestication, retaining most of the living habits of wolves. They respect authority and fight among themselves. Even if you keep a dog at home without a pack, the family still forms a group. Naturally, the dog will regard the head of the household as its "king" because it has been raised by humans, so it will not challenge the king's authority and can only obey. However, this alone is not enough to explain the saying "a dog looks down on people." In many animal groups, even if they are not from the same clan, the authority of the king from another group is also beyond doubt. By comparison, a dog's behavior when it encounters a strange child versus a strange strong man is very different.

If it is a strange child, the dog may rush up to bite, but if it is a strange strong man, it rarely rushes forward, as it dare not challenge out of instinct. This habit is also an instinct of all animals, including humans. To summarize, it means bullying the weak and fearing the strong.