 There is no inconsistency in the coexistence of these two families of principles, for they are not in direct conflict with each other. Considerations of parsimony and of explanatory sufficiency function as mutual counter-balances, penalizing theories which stray into explanatory inadequacy or ontological  excess.[23]  What we see here is an historical echo of the contemporary debate among statisticians concerning the proper trade-off between simplicity and goodness of fit.