Le 10 mai à 19:12:16 Kevin Hoover <[log in to unmask]> écrit notamment:

| Can anyone point to the earliest account of the distinction between
| substitutes and complements -- conceptually, if not in those very
| words?

Cournot's Researches chap. IX «Du concours des producteurs» (1838) is
perhaps the earliest text theorizing complementarity in production.  

His emphasis is not on the contrast between complementary
vs. substitutable inputs, but on the contrast between complementarity of
producers on the one hand and competition between producers (as appears in
his theory of oligopoly) on the other hand.

I hope this may help anyway.

Regards,
-- 
  Jean Magnan de Bornier   |   Professeur de Sciences Économiques
         GREQAM	           |  Université d'Aix-Marseille 
 15-19 Allée Claude Forbin |   13627 Aix-en-Provence Cedex 1 FRANCE 
 T: +33 (0)4 42 96 81 53   |   email: jean.magnanb at univ-amu.fr  
 Fax: +33 (0)4 42 96 80 00 |  Site: http://junon.univ-cezanne.fr/bornier