Gentleman, the boy going in after his dog was 16 years old. Some of you are approaching this as if he had the reasoning skills of an older man with life experience behind him that would have helped him to make a more rational decision. What sort of clear-headed decision would any of us had made at this age in this particular situation under the same circumstances?
He saw a pet that he presumably loved very, very much in what he thought was a life-threatening situation, and he more than likely gave very little thought if any to his own safety when he went in after the dog. His action was reactional instinct to a stressful situation. His thought process probably went no farther than "my dog is in trouble and I need to save him" and nothing more or nothing less.
This is what young people do. They make many mistakes in their formative years which is how most of us learn how to successfully deal with situations later in life, but unfortunately in this case, it was a fatal mistake.
To draw any conclusion that the boy considered the dog his equal is merely conjecture. The conclusion we can draw however, is that he loved his dog. That is the most admirable part of the tragic story.