How Lives Measure Up

The quality of a life is typically understood as a function of the actual goods and bads in it, that is, its actual value. Likewise, the value of a population is typically taken to be a function of the actual value of the lives in it. We introduce an alternative understanding of life quality: adjusted value. A life's adjusted value is a function of its actual value and its ideal value (the best value it could have had). The concept of adjusted value is useful for at least three reasons. First, it fits our judgments about how well lives are going. Second, it allows us to avoid what we call False Equivalence, an error related to the non-identity problem. Third, when we use adjusted value as an input for calculating the value of a population, we can avoid two puzzles that Derek Parfit calls the "Repugnant Conclusion" and the "Mere Addition Paradox.".