Question

moral of white fang in short

Answer 1

the moral can be said like this
try an opinion or two, start a debate, or play the devil's advocate

Answer 2

Certainly what White Fang learns falls in line with London's theme of naturalism. He learns his true calling lies in his hereditary position of dog of the wild. White Fang's heredity is carefully defined, "one-fourth dog, three-fourths wolf," leading up to the struggle within him between his civilized impulses and his wild ones. London is also particularly careful to adhere to established facts of a wolf's life cycle in White Fang's early years. White Fang learns the law of the wild is a Darwinian sort of place (he learns this in his own doggy way!). White Fang also learns lessons of trust and loyalty.