In economic and financial theory, the explains why interest exists and how its rate is determined within a market. It essentially treats interest as the "price of time"—the compensation paid to a lender for postponing their own consumption and assuming the risk of lending capital to a borrower. Core Conceptual Frameworks
Different schools of thought provide varying perspectives on why we pay for the use of money: Theory of Interest
: Posits that the interest rate is an equilibrium point where the supply of savings (from households) meets the demand for investment (from firms). It views interest as a "reward for waiting" or abstinence from immediate spending. In economic and financial theory, the explains why
: Argues that interest is not a reward for saving, but a reward for parting with liquidity . According to John Maynard Keynes , people prefer holding cash for its safety and flexibility; interest is the premium required to convince them to hold less-liquid assets like bonds. It views interest as a "reward for waiting"
: The baseline compensation for the time value of money, often based on government securities.
: Championed by Eugen von Böhm-Bawerk , this theory emphasizes that humans naturally value present goods more than future goods (agio). Interest is the "discount" applied to future satisfaction. Fundamental Mathematical Components