21世纪社会民主和社会主义模式的政治经济学分析:继续探讨大卫·哈维提出的问题

David Harvey's The Enigma of Capital takes a multi causal approach to maintain various types of crisis theory in Capital for explaining why and how capital inevitably forms a capitalist market economy intrinsically crises一ridden. Following up his framework, this paper intended to complete a basic theory of classical cyclical crises of labour shortage type together with Marx's theory of credit system and use this theory to analyze exactly the reasons and results of the global inflationary crisis at the beginning of the 1970s. After comparing 21st century models of social democracy with socialism, this paper discussed four candidates of promising strategies for them, which are keynesiamsm, green-recovery, basic income and local
currencies. These four candidates are considered to be foundation and theoretical significant for new developments in the 21st century models of strategies for radical social democracy and socialism.