In the classical period of Adam Smith, economics originally had a coincidence between wealth growth and human happiness, that is, the rational self-interest choice of rational people tending to avoid harm was subject to economic ethics. It was the self-interest under the premise that Pareto improved the conditions without harming others. But economics itself assumed the task of maximizing the interests of the subject, and it continued to introduce mathematical tools and analytical methods of abstract logical deduction, which made economics more Increasingly, it has become a discipline where instrumental rationality prevails, and it is moving towards the trend of "neutral", "non-value" judgment, and "non-moral" choice. From this text, we can know:. ['Economic ethics is becoming less restrictive on economics.', 'Classical economics does not use the method of abstract logical deduction.', 'In the time of Adam Smith, economics was a discipline dominated by instrumental rationality.', 'The introduction of mathematical tools breaks the connection between wealth growth and human happiness.']