 Another way of modifying total utilitarianism is to introduce a critical level (Kavka 1982, Parfit 1984; Locke 1984; Blackorby et al. 1997, 2004, 2005; Broome 2004). As is the case with the variable value view, a critical level view is based on a split between prudential and moral value. However, in this case the split is even more radical. The idea is that a person’s life contributes positively to the value of a population only if the quality of the person’s life is above a certain positive critical level. Below this level the contributive value of a life is neutral (Kavka 1982), negative (Blackorby et al. 1997, 2004, 2005; cf. Feldman’s theory below), or introduces incommensurability or vagueness in the ordering of populations (Blackorby et al. 2005; Broome 2004; Rabinowicz 2009; cf. Parfit 2016), even though the person leads a life worth living. In its simplest form, the critical level view is a modified version of total utilitarianism. The contributive value of a person’s life is her welfare minus a positive critical level. The value of a population is calculated by summing these differences for all individuals in the population. The critical level view thereby succeeds in avoiding the Repugnant Conclusion. Assuming the critical level is higher than the individual welfare levels in population Z, the Repugnant Conclusion is blocked since the value of Z is negative, and thus worse than A, according to the critical level view.