An axiomatic approach to measure the 'Leave no one behind' principle.

'Leave no one behind' has become an important principle of the entire 2030 Sustainable Development Agenda and the Sustainable Development Goals that brings inequality to the centre stage. Although a precise definition of what it is to lag behind is essential to assess sustainable economic growth and social progress a discussion on the desirable properties of such a measure is absent in the literature. This paper fills that gap by proposing and discussing a number of normative and analytical properties a measure of the 'Leave no one behind' principle should satisfy. The axioms proposed are necessary and sufficient to characterize the fuzzy measure by García-Pardo et al. [8] and together with other additional axioms make the structure of this measure more transparent. • Leaving no one behind is the central focus of the Sustainable Development Goals. • The Leaving no one behind principle suggests going beyond the averages. • The ambiguity of the left behind principle makes it convenient to use a fuzzy approach. • We discuss desirable properties of a measure of the extent an individual lags behind. • A subset of axioms characterizes the fuzzy set proposed by García-Pardo et al. [8]. [ABSTRACT FROM AUTHOR]