“… the rate of interest is the reward for parting with liquidity for a specified period. For the rate of interest is, in itself, nothing more than the inverse proportion between a sum of money and what can be obtained for parting with control over the money in exchange for a debt for a stated period of time.
Thus the rate of interest at any time, being the reward for parting with liquidity, is a measure of the unwillingness of those who possess money to part with their liquid control over it. The rate of interest is not the ‘price’ which brings into equilibrium the demand for resources to invest with the readiness to abstain from present consumption [!]. It is the ‘price’ which equilibrates the desire to hold wealth in the form of cash with the available quantity of cash” (Keynes, 2013, p. 165; grifo meu)
Taxas de Juros são, para Keynes, o preço que um indivíduo está disposto a pagar para desfazer-se da liquidez de sua riqueza, em prol de ativos menos líquidos (i.e. que rendam mais que ).
É, portanto, como consequência disso que A taxa de juros é o custo de oportunidade do dinheiro presente vis-à-vis dinheiro futuro.
References
- KEYNES, John Maynard. The collected writings of John Maynard Keynes: The General Theory of Employment, Interest and Money. Cambridge: Cambridge University Press for the Royal Economic Society, 2013. v. 7.