Dude, Tolstoy did not write The Brothers Karamazov. Get things straight. Besides, part of his point was that these cruelties are hidden-- how could he go help the said children if he could not find them? Plus, how could he possibly help them all? He is upset at god that these events occur in the first place-- what good can Ivan possibly do with all his "wealth and privilege" once the children are already tortured? No matter what he does, it doesn't erase the existence of the traumatic event.