On 8 Jul 2004 at 19:56, Humberto Barreto wrote: > My answer to the original question would be, "It depends. Do you mean > indifference in a general sense or do you mean indifference in the > sense of a contour line or level curve?" Bert has in my view correctly framed the serious issue. The original query, while innocuous sounding, was ill-posed. We have known certainly since the early 1960s, with Kuhn's question " Did Priestley or Lavoisier 'discover' oxygen?", that concepts change even as their labels do not, and that as the full context of a scientific idea, the 'paradigm' in which it functions, changes, so does the idea, so that there are possible incommensurabilites between apparently identical concept-words. It is thus historically non-trivial to ask about the first use of concept-word X, and one of the roles of an historian is to provide a rich contextualizing discussion of that word-concept. My own partial attempt to get at the problem Bert identified was in "Is 'Is a Precursor of' a Transitive Relation?", South Atlantic Quarterly, 94:2, pp. 571-589, 1995. [Reprinted (in a different form) in Andrea Salanti and Ernesto Screpanti (eds.) Pluralism in Economics: New Perspectives in History and Methodology. Cheltenham, UK: Edward Elgar, 1996, pp. 212-226. Reprinted in Barbara Herrnstein Smith and Arkady Plotnitsky, (eds.) Mathematics, Science, and Postclassical Theory. Durham, NC: Duke University Press, 1998, pp. 173-188.] E. Roy Weintraub Duke University