This essay concerns the status of explanations of social change raised by John Fairweather's discussion of settler colonial development in New Zealand (1985). He opposes his own 'internalist' theory of the organisational dynamic of capital investment in pastoral economy, to an 'externalist' perspective he attributes to me, among others, characterised as 'class-based explanations of changes in agriculture' (1985, 238). What I attempt is to critique Fairweather's organisational focus as economistic and governed by a belief in technical rationality. I also respond to his caricature of my argument by restating it and examining why his own epistemology produces caricature. His 'internalist'/'externalist' dichotomy of explanations reveals the limits of an undialectical materialist analysis of the arrangement of factors of production. Thus he claims that 'the key to explanation of colonial development is the role of land and capital in pastoral capitalism' (Fairweather, 1985, 238).