 The blocks above represent two populations, A and Z. The width of each block shows the number of people in the corresponding population, the height shows their quality of life or lifetime welfare. All the lives in the above diagram have lives worth living. People’s quality of life is much lower in Z than in A but, since there are many more people in Z, there is a greater quantity of welfare in Z as compared to A. Consequently, although the people in A lead very good lives and the people in Z have lives only barely worth living, Z is nevertheless better than A according to total utilitarianism. Thus, the attempt to provide a plausible solution to the Non-Identity Problem has led to a seemingly unacceptable conclusion.