Explanation:

- The phrase "From each according to his ability, to each according to his needs" is most often associated with Karl Marx. It epitomizes the Marxist principle that people should contribute to society based on their abilities and receive based on their needs.

- David Ricardo was a classical economist known for his theories on rent, wages, and profits, and the concept of comparative advantage in trade.

- John Stuart Mill was a philosopher and economist known for his work on utilitarianism and liberty, advocating for individual rights and economic freedom.

- Adam Smith is often called the father of economics, known for "The Wealth of Nations" and his advocacy of free-market policies.