We develop a theory of money and credit as competing payment instruments, then put it to work in applications. Buyers can use cash or credit, with the former (latter) subject to the inflation tax (transaction costs). Frictions that make the choice of payment method interesting also imply...

Conventional wisdom is that inflation makes people spend money faster, trying to get rid of it like a “hot potato,” and this is a channel through which inflation affects velocity and welfare. Monetary theory with endogenous search intensity seems ideal for studying this. However, in standard...