This article analyses the relationship between the concept of single aspect similarity and proposed measures of similarity. More precisely, it compares eleven measures of similarity in terms of how well they satisfy a list of desiderata, chosen to capture common intuitions concerning the properties of similarity and the relations between similarity and dissimilarity. Three types of measures are discussed: similarity as commonality, similarity as a function of dissimilarity, and similarity as a joint function of commonality and difference. Relative to the (...) desiderata, it is found that a measure of the second type fares the best. However, rather than recommend this measure alone as a measure of similarity, it is suggested that there are at least three separate concepts of single aspect similarity, corresponding to the three types of measures. In light of this proposal, three of the eleven measures (and variants of these) are deemed acceptable. (shrink)

In this essay I propose a new measure of social welfare. It captures the intuitive idea that quantity, quality, and equality of individual welfare all matter for social welfare. More precisely, it satisfies six conditions: Equivalence, Dominance, Quality, Strict Monotonicity, Equality and Asymmetry. These state that i) populations equivalent in individual welfare are equal in social welfare; ii) a population that dominates another in individual welfare is better; iii) a population that has a higher average welfare than another population is (...) better, other things being equal; iv) the addition of a well-faring individual makes a population better, whereas the addition of an ill-faring individual makes a population worse; v) a population that has a higher degree of equality than another population is better, other things being equal; and vi) individual illfare matters more for social welfare than individual welfare. By satisfying the six conditions, the measure improves on previously proposed measures, such as the utilitarian Total and Average measures, as well as different kinds of Prioritarian measures. (shrink)

This essay introduces a new type of measure of social welfare, where populations are evaluated by their resemblance to an optimum population, which is an (in principle) possible population with the highest degree of social welfare, relative to some circumstances. Here it is argued to be the largest possible population where everyone fares maximally well. The new measure is responsive to quality of welfare, equality of welfare, and the number of people. It satisfies dominance and negative monotonicity, and it avoids (...) both the repugnant conclusion and a reverse repugnant conclusion for comparisons relative to our future on earth. (shrink)

In this essay I argue that even though egalitarianism and prioritarianism are different theories of social welfare, they can use the same social welfare measures. I present six different arguments for this thesis. The first argument is that conceptual connections between egalitarianism and prioritarianism ensure that any measure that works for either theory works for both. The second argument is that conditions necessary and sufficient to identify egalitarian and prioritarian measures, respectively, are equivalent. The third argument is that both egalitarianism (...) and prioritarianism can use two standard measures, typically proposed for only one theory. The fourth to sixth arguments contend that four properties that have been proposed as distinctive of either egalitarian or prioritarian measures cannot distinguish between them. I conclude that any egalitarian measure is also a prioritarian measure, and vice versa. (shrink)

The thesis studies the problem of measuring freedom of choice. It analyzes the concept of freedom of choice, discusses conditions that a measure should satisfy, and introduces a new class of measures that uniquely satisfy ten proposed conditions.

In this essay I discuss a person’s freedom to choose whatever that person may reasonably prefer to choose. This type of freedom of choice may be regarded as a candidate for a social good, being a hybrid between freedom of choice and preference satisfaction utility. To separate this preference dependent freedom of choice from other types, we may call it opportunity. The essay is concerned with the question of how opportunity should be identified and measured. I discuss what conditions an (...) opportunity measure should satisfy and propose that an opportunity measure should satisfy at least four specific conditions. I then present a new class of measures which satisfy the four conditions (the Root measures). Last I prove that these measures are the only ones that satisfy the conditions, given the extra assumption that the measures are analytic functions with non-zero partial derivatives. (shrink)