The reciprocal interaction of physical and social technologies exhaustively explain economic evolution. 2. Natural science theories like Darwinism inspired the further understanding of changes in the economy. 3. Great economists like J. Schumpeter were committed to the research on economic and biological theories. 4. The mainstream paradigm of economics over the past hundred years gradually turned to physics. 5. According to the text, economics firmly believe that a whirlpool and an ant clan are intrinsically consistent with scientific theories.