REGULAR ARTICLE Upward and downward complementarity: the meso core of evolutionary growth theory Kurt Dopfer 1 & Jason Potts 2 & Andreas Pyka 3 # Springer-Verlag Berlin Heidelberg 2015 Abstract We propose that the concept of complementarity can take two distinct meanings in evolutionary economics: one referring to Adam Smith’ s notion of increas- ing specialization and the division of labour, which we denote ‘downward comple- mentarity’ (wholes into new parts); and a second type that refers to the discovery of emergent complementarity between extant or new components and products, which we call ‘upward complementarity’ (parts into new wholes). We outline this new conception and explore some of its analytic and theoretic implications. Keywords Complementarity . Economic evolution . Division of knowledge . Division of labor . Meso economics . Entrepreneur . Unified evolutionary growth theory JEL Classification B52 . E14 1 Complementarity in generic and operant analysis Progress in science often takes the form of either: (a) realizing that things thought to be different are actually similar; or (b) realizing that things thought to be similar are actually different. Neoclassical economics is often at its best in the first mode seeking topological equivalence of the structure of different decision problems: for example when Theodore Schultz and Gary Becker showed that what appeared to be qualitatively different phenomena—investment in plant and factories and educating children—could both be studied as investment in capital. But evolutionary economists have long been at their best when operating in the second mode of elaborating differences. The basic J Evol Econ DOI 10.1007/s00191-015-0434-4 * Jason Potts jason.potts@rmit.edu.au 1 University of St Gallen, St Gallen, Switzerland 2 RMIT University, Melbourne, Australia 3 Hohenheim University, Stuttgart, Germany