What is the main contribution of Ricardo to the progress of economic science?

Ricardo proposed the theory of comparative advantages, which defends free international trade and responds very well to the requirements of England in the early 19th century as the first country in the process of industrialization.
Ricardo analyzed the nature and conditions of a country to make certain goods and proposed the theory of compared costs based on laissez faire.
Ricardo constructed a solid analytical structure for classical political economy, which constitutes his main contribution to the progress of economic science.