"What about contentment (acquiescentia) during life? - For the human being it is unattainable: neither from the moral point of view (being content with his good conduct) nor from the pragmatic point of view (being content with the well-being that he intends to secure through skill and prudence). As an incentive to activity, nature has put pain in the human being that he cannot escape from, in order always to progress toward what is better. . . . To be (absolutely) contented in life would be idle rest and the standstill of all incentives, or the dulling of sensations and the activity connected with them. However, such a state is no more compatible with the intellectual life of the human being than the stopping of the heart in an animal's body, where death follows inevitably unless a new stimulus (through pain) is sent."