 The vague open-ended term “diversity”, in the CBD definition, can be interpreted as any of a number of ecological diversity indices (see below). In contrast, IPBES reflects pre-history in shifting to the word, “variation”. Naturally, this word has provided its own interpretation challenges, including how to characterise it consistently across different levels of variation. Weitzman (1992) presented an influential general framework for biodiversity as variation, based on the idea of objects, and measures of difference between objects. Biodiversity (amount of variation) then depends not only on the number of objects, but also the degree of differences among them. In the book Philosophy and Biodiversity, the link between “biodiversity” and investment and insurance value is described as depending on: “The higher the number and the degree of difference between biological elements” (Koricheva &amp; Siipi 2004: 39). Weikard (2002) argued that any operational concept of biodiversity must have some measure of difference between objects (see also Maclaurin &amp; Sterelny 2008; Morgan 2009).