What is the relationship between artistic movements and the historical periods during which they first appeared? Can the methods associated with these movements be detached from their original context for the benefit of later artists? Do the answers to these questions depend on which movements and periods we are discussing? The issue is of more than academic interest. Serious contemporary artists want to produce work relevant to, and critical of the societies in which they live; but in doing so, are they free to draw on any methods, from any point in history, or will only some be adequate to their needs? Should socialists expect them only to work with particular methods, and criticise them when they do not?