Imprisoning oneself inside his own history; inside what he has always believed, what folks around him believe and proclaim; can’t reach very far into deep, pure, meaningful understanding. Learning to observe carefully with his senses, and to do so objectively, carries him much further in. Scientific understanding could conceivably carry him further still, and then deep spiritual attunement even deeper. But he doesn’t get there by taking any one single step; he doesn’t reach deepest knowing by locking himself into one level.
He gets there by letting go of it all.