Causes for the distinct and growing separation of the academic domains of economics and neighboring fields are ongoing processes of specialization, fragmentation, and evolution. Thanks to the proliferation of publications and knowledge in economics, degrees of specialization have emerged. One of the great paradoxes in economics is the existence of mainstream economics, which is taught to undergraduate students and dominates textbooks, alongside new contributions that enter the arena via other disciplines (e.g., psychology, history, and law). The paper delineates some developments in economics over the last 100 years oscillating between continuity and change. Especially, the interplay between different domains in the social sciences is discussed as fields of tension and cooperation between economics and other disciplines. The message of the article is that economics is not a homogeneous body of being, content, and learning. Economics has a diverse knowledge base on a theoretical and methodological level with different forms of economic capacity, conceptual sensitivity, and methodological rigor. Many different approaches coexist with corresponding camps of authors. A multiplicity of topics and discourses can be observed with an interesting division of economics with one branch focused on mathematics, econometric tools, and applications, and the other branch moving towards increasing social scientification with strong links to psychology, history, philosophy, and sociology. The Oxford credo of politics, philosophy, and economics (PPE) has undergone a revival in this respect.
