Figure 1: Liquidity preference theory of Keynes Source: (created by author) On the contrary, the concept of bond market can be derived from loanable funds and this is an extension of classical theory (Fiebinger and Lavoie 2018). According to the next Keynesian market theory, which can be derived from loanable theory and Keynesian theory of liquidity preference. According to the next Keynesian market theory, which can be derived from loanable theory and Keynesian theory of liquidity preference.