One example is that the dog still recognized the owner even if it was twenty years since they have last seen each other. This means that the dog had a strong friendship with the owner when the owner was still there.Twenty years is a long time for dogs.
Another example is when the article says,"'Infested with ticks, half dead with neglect' and lacking the strength even to drag himself toward his master, Argos thumped his tail, nuzzled low, and dropped his ears in grateful recognition. Then the 'dark shadow of death closed down on Argos’ eyes.'"When he met his owner, Argos got into a respectful position for his master, but instantly died. It's like if the dog was waiting for him for twenty years.
This story was very touching. This dog lived longer than they're suppose to live. This dog was also neglected. He was half dead when he met his owner. It was like he was bowing for his master, then died to rest in peace.