Is it that people have so many hidden motivations you become suspicious, or worry about generating / reciprocating feelings of obligation, or end up disappointing you after causing you to invest emotion?
Or just that a "simple" animal can exhibit such complex behavior that we find especially endearing?
I don't think it's really as universal as that and depends a lot on the cultural norms and the specific manifestation of loyalty.
A good example would be the common misconception of the Samurai ethos in Western circles. Many people cite the Hagakure [0] and Bushido [1] like they are some kinds of manuals for a bad-ass Samurai making their own way through strong principles, perfectly fitting the pop-culture depictions.
When in reality, these books describe the Samurai as the most loyal retainer to his daimyo, who holds up his strict principles not out of vain/self-glorification, but because that was considered the best way to serve his master, which was considered the most important thing to them.
It's an ethos about loyalty to the point of self-sacrifice for the master's honor, which doesn't hold up very well in our modern hyper-individualistic times.
[0] https://en.wikipedia.org/wiki/Hagakure
[1] https://en.wikipedia.org/wiki/Bushido:_The_Soul_of_Japan
One of my favorite Japanese films, Samurai Rebellion, explores the clash between principles and loyalty. It features Toshirô Mifune, and some amazing costuming.
And then there's Takasi Miike's 13 Assassins :)
One of my
Western circles often mistakenly believe the Hagakure truly embodies the Samurai spirit, when in practice most Samurai didn't follow it and weren't as selfless or honor-bound as the code would have you believe.
Unlike with humans, we think of animals as being incapable of having hidden motives. Which is wrong by the way, dogs can be sneaky bastards. Not only you probably noticed it if you own a dog, but it has been scientifically studied ( https://link.springer.com/article/10.1007/s10071-017-1078-6 ).
In the particular case of Hachiko, it is worth nothing that he was fed for nine years. Extreme loyalty or not, he had every reason to continue what he was doing.
But why is the story of Hachiko so endearing? Because it is a tale. The truth is probably somewhere between the story of boundless loyalty we love to tell, and that of a stray dog that found a particularly effective way of scoring food. But who cares about the truth, it doesn't make a good story.
Edit: I noticed I was pretty dismissive... Note that I really believe that loyalty is a thing with dogs. But I also think we tend to underestimate their survival abilities around humans.
Food is the major reward signal for animal training, so it’s a sensible theory.
e.g. if you want to be able to get their full potential and have an outcome where you can trust them to never pick up food from the street, never accept anything from a stranger. Training them with food you will never get to a level where you can leave them alone with raw meat next to them, then leave for 2 hoursand KNOW the food will still be there untouched when you get back.
we had a border collie who past away some time ago, and she was extremely food driven. She lived few months on the street until I found her. She was happy to obey until she smelled food then she would no longer listen (once she ran across a busy street because there was a garbage bin on the other side of it ... Even she was still less than 1 yro when she came to us I was never able to get that out of her.
I raised also several Belgian Malinois (all from the same litter). We had them just after they turned 3 months so they could learn as much as possible from their mother and siblings before they came to us.
3 of them I never even had to bother using treats as a reward because they were so "hungry" for verbal praise. All the dogs I had, the Malinois were unique as they all shared this crazy possession for praise. They were so smart that when left alone they would just go in the garden by themselves and play "I throw sticks into the water and then jump in to rescue them", and they entertained themselves like this for several hours (usually until I had to tell him to get out because it got dark).
They never received a treat during training and I could switch to clicker really soon. All the Malinois coming from the same stock (all siblings). 1 of them would have little interest in my praise during training but learned very well when using his prey-drive as a motivator (e.g. the reward was to throw a ball as soon as they do something correct).
It depends on the animal but breed is less important than character and age. Also dog training is never about training the dog but training the owner to respond correctly to the dog. I recommend everyone who owns dogs who are still at the puppy age to get them off food treats asap and get a lot better results out of them.
People don’t think this way about dogs (maybe they do about cats).
The human-dog relationship is also well-defined. Play, feed, house, take for walks. Your dog is not suddenly going to ask for a romantic relationship or con you into loaning them money. Closeness is just less risky.
If both are alive, yes, both when one of they is dead, the other(s) loyal person(s) may still serving an extra dish at the table for years, or keeping their room intact.
I know it's a psychological condition and all, but is the most similar behavior comparing it to the dog's.
The wifes of Decabrists were following their stripped of any nobility husbands into exile to Siberia, in some cases leaving their children. As a result these women were also stripped of nobility and as a family left without any income apart from work.
There is even a term "жена декабриста" (decabrist's wife) in Russian culture, which describes extreme loyality of the wife to her husband.
These are all good, but the one that strikes me first is this:
Part of the value of having a relationship with someone is that they are a competent being in their own right. If they stick with someone when it is clearly not in their self interest (e.g. not caring for a disable spouse, but putting up with abuse), even if that abuse is at your own hand, the value of that person drops in your estimation.