Adhering to the methodology of dialectical materialism , the author raised the dual character of labourforce and natural resources , the dual character of abstract and concrete labour , the dual character of exchange value of commodity and the dual character of money , whereupon the essence of surplus value is analysed and 9 formula by which the production value of commodity is transformed into commodity price are discussed 在坚持辩证唯物主义的方法论中，提出了劳动力与自然资源的二重性，抽象劳动与具体劳动的二重性，商品交换价值的二重性，货币的二重性，分析了剩余价值的实质，研究了商品生产价值转化为商品价格的9种公式。
