In this chapter I directly respond to the problem statement of the book by showing that in order for our existence to have meaning it must have the feature of willpower — the ability to exert effort. But the feature of willpower implies a system of energy transformation, and a system of energy transformation, in turn, implies the possibility of suffering and death.
From chapter 5 on developing ethical principles, we know that we obtain meaning in life through relations with other people. But what can we do in these relations to obtain meaning? We balance egoism and altruism in the context of human mortality. In everyday terms, we realize meaning by helping other people survive as we work to survive. I refer to this balancing feature as the meaning tradeoff.
These results are fascinating because they mean that if a competent designer wanted to design a meaningful life for a race of intelligent free agents, they would end up with the fundamental features of human life. There aren't any other choices.
Reference citation. Philip Bitar, adapted from Why Human Life Makes Sense, Editions 1/2/3, 2011/2012/2015, p. 56-57/62/380, posted at www.WhyHumanLifeMakesSense.com, 2011-08-26.