Edwin Cannan, a largely forgotten classical bourgeois economist from the Ricardian school of the early 20th century, could be described as the last of the classical political economists and, as such, shared with Marx certain economic views, in particular that inflation was a purely monetary phenomenon caused by an excessive issue of an inconvertible paper currency and that banks were merely financial intermediaries without any power to "create credit."
Hardcastle's empirical bent enabled the SPGB to refute, with the necessary statistical evidence, theories which have sometimes been attributed to Marx such as underconsumptionism, the increasing pauperisation of the working class, the collapse of capitalism (Hardcastle was the author of the famous 1932 SPGB pamphlet Why Capitalism Will Not Collapse[3]) and—more controversially within the Party—the increasing severity of economic crises.
Hardcastle gave a great input into the SPGB, particularly to the Socialist Standard, serving on the editorial committee for over thirty years and contributing articles from the early 1920s onwards.
[4] Towards the end of his life, Hardcastle found himself a member of one of two branches which were expelled by a poll of all the membership for deliberately and repeatedly refusing to apply a democratically arrived-at Conference decision.
The two expelled branches went on to form the Socialist Studies group in 1991, of which Hardcastle remained a member until his death some four years later.