One makes one's nature by one's likes and dislikes, by what one favors or disfavors. When a person says, "I don't like this food", he has built something into his nature; and then that food, when eaten, will often disagree with him. It is not that it was meant to disagree with him, but he made it disagree by disliking it. By control, bravery, endurance, steadiness, by all such qualities one makes one's nature either agreeable or disagreeable. Either one makes one's nature as hard as a rock, a rock that will not allow anything to pass, or one makes one's nature as pliable as water.