Quadragesimo Anno §42

⁴² Even though economics and moral science employs each its own principles in its own sphere, it is, nevertheless, an error to say that the economic and moral orders are so distinct from and alien to each other that the former depends in no way on the latter. Certainly the laws of economics, as they are termed, being based on the very nature of material things and on the capacities of the human body and mind, determine the limits of what productive human effort cannot, and of what it can attain in the economic field and by what means. Yet it is reason itself that clearly shows, on the basis of the individual and social nature of things and of men, the purpose which God ordained for all economic life.