Viktor Winschel has studied economics and has received his PhD from the University of Mannheim in 2005 on the theory of exchange rate regimes, optimal currency areas (like or unlike the Euro zone) and econometrics. A core feature or problem therein are circularities (or self-references or reflexivities) that naturally arise in societies and humans who reason about each other. Circularities, like sets containing themselves, are not handled in standard mathematics and mathematical economics but have been developed in theoretical computer science for the semantics of programing languages. Viktor is now adopting these tools based on category theory and coalgebras for game theory, macroeconomics and econometrics in order to accomodate the circular nature of money and its aspects of belief and network formation, epistemics, reputation, value creation, securitization or speculative attacks on central banks.