G.A. Cohen (1988, p. 84): 'The tendency's autonomy is just its independence of social structure, its rootedness in fundamental material facts of human nature and the human situation.' Allen Wood (2004, p. 75): 'Historical progress consists fundamentally in the growth of people's abilities to shape and control the world about them. This is the most basic way in which they develop and express their human essence' (see also, the quotation from Allen Wood above).