how the dog knew that his master is dead ?

Hachikō may or may not have known his master was going to die. There are hundreds of anecdotes about how a dog seemed to "know" some human was sick or about to die. Years ago, my own dog seemed to know when I had a stomachache, and she would quietly, almost apologetically, rest her snout on the place that ached the worst. Until we can communicate clearly with dogs, these kinds of stories will just make you go "hmmm." And nothing more.

The one thing we can be sure of with dogs: they are creatures of routine and habit. What is familiar, what is known and predictable, that is what a dog will choose day in and day out. Hachikō waited for his master to get off the train (even though the master had died) every day for about 9 years. This strongly suggests that the dog didn't know his master had died, or else the dog understood death very poorly.

Hachikō may or may not have known his master was going to die. There are hundreds of anecdotes about how a dog seemed to "know" some human was sick or about to die. Years ago, my own dog seemed to know when I had a stomachache, and she would quietly, almost apologetically, rest her snout on the place that ached the worst. Until we can communicate clearly with dogs, these kinds of stories will just make you go "hmmm." And nothing more.

The one thing we can be sure of with dogs: they are creatures of routine and habit. What is familiar, what is known and predictable, that is what a dog will choose day in and day out. Hachikō waited for his master to get off the train (even though the master had died) every day for about 9 years. This strongly suggests that the dog didn't know his master had died, or else the dog understood death very poorly.