土地生产率极限法则和中国的隐性农业革命

The Law of Limit to Land Productivity and China’s Hidden Agricultural Revolution

本文首先用土地生产率极限的新概念建立起一个从空间上由物质、经济和制度三个世界组成,及从时间上能揭示人口陷阱前、人口陷阱中和人口陷阱后三个不同发展阶段的反向逻辑的土地使用动态模型。此模型把马尔萨斯人口模型从原来只能解释工业革命前的历史拓展到也能解释工业革命后的历史,并把诺斯的主观唯心的静态产权理论改正为一个客观唯物的动态土地产权理论:(1)成本回报率决定土地产权的作用;(2)成本回报率的变化改变土地产权的作用;(3)劳均土地资源的变化先改变成本回报率,其次才改变土地产权模式。依据此模型的构架和中国的历史统计数据,本文接着从供给角度去验证和充实黄宗智先生最近提出的中国隐性农业革命,并同时验证这一模型的各组反向逻辑和动态土地产权理论。本文的验证结论是诺斯的只有制度世界和经济世界的静态产权理论颠倒了事物的因果关系。国家虽然能决定选择何种产权制度,但无法控制何种效果会从它选择的产权制度中产生出来,因此就应按照产权制度的真实效果而非诺斯理论主观臆想的效果来选择具体的产权制度。

By a new concept,the law of limit to land productivity,this paper builds a three(physical,economic andinstitutional)worlds’land-use model with inverse logics of different development stages before,in and after the population trap,which extends the span of Malthusian population model to history after the industrial revolution and makes the static property rights theory dynamic:(1)cost/return ratios decide effects of land rights;(2)changes in cost/return ratios alter effects of land rights;(3)changes in land/labor ratios first alter cost/return ratios and next patterns of land rights.By this model and statistical data,the paper then from the supply side substantiates China’s“hidden agricultural revolution”advanced by Huang,and simultaneously tests the model’s inverse logics and dynamic land rights theory.The test result is that Douglass North’s property rights theory has reversed causality of things,and the state can decide to choose what kind of property regimes but cannot decide what kind of effects will flow from the regime chosen by it,and hence should select property regimes according to their real effects rather than the effects made subjectively by the North“theory”.