"He's got dog in him"

I don't say this unironically very often but this is a pretty interesting thread. And I don't know the answer. I am going to offer a possible explanation before the actual one from people who know things and can find things out will show up and ruin it for me. Anyway, it makes me think of something of a rhetorical analog to convergent evolution like bats and birds and their ability to fly. Or, say, Charlie Sheen and a plane and their ability to fly. It's possible that because people from areas that have bred dogs for more violence and aggression or simply utilized them toward that end, as literal fighting dogs, or the most vicious junkyard types of watch dogs, whatever, implied someone had dog in them separately in the sense of having the fighting spirit while others unaccustomed to these breeds and utilities for them are only familiar with the meeker and milder dog behaviour and mean it in a sense that they will cower when someone or thing seems more likely the dominant one in the vicinity?

So, it became a saying, mayhaps, in two different groups of people, and even means two completely different things from each group, rather than one intention that turned into another completely. Incidentally, where I am from, we also hear about an admirable dog "He's got that wolf in him."

Maybe this should be edited into the original post for people who shamelessly somehow have valuable input but also won't read past the OP before commenting. As I often do and don't.

 

When people used to fight pitbulls, they would keep the dog that kept living even though he was losing to the more agressive pitbull.

they would discard the more aggressive pitbull


That’s according to my friend that used to watch illegal dog fights.

 

Correct. I’ve seen it used for years in Boxing to mean a quitter. Not sure when this change was made but when I call someone a dog it means they have no heart and are a quitter.

 

The first person I can remember using it as a compliment was Kellerman which should be no surprise since he’s a god damn idiot. For decades I can remember all the boxing announcers using it to mean little to no heart and a quitter.

 

Coward. Lying down, turtling, wimpering like a dog

 

It is not the size of the dog in the fight, it is the size of the fight in the dog.

 

I think I remember Don King saying McClellan quit like a dog.

 

Here in Australia it means cowardice or unflattering still.

A police informant in Australia is called a “dog” like they call them a “snitch” elsewhere.

The term running like a “whipped cur” Is a dog reference and it doesn’t mean courageous thats for sure.

 

When I call or hear someone call a person a dog it’s an insult. It ain’t a compliment

 

Upon further reflection a turning point might have been the song "who let the dogs out".

 

Younger generations all call each other dogs so careless and humorous these days. I remind them calling someone a dog was proper fighting words not that long ago. Proper condemning someone's character

 

Civil War references lol.