Summary of General Theory Book IV Chapter 15 Section II

In section 15.2, Keynes elaborates on the idea that the different motives informing liquidity-preference are influenced differently by different factors.He says that $M_1$, the money savings corresponding to the transaction-motive and precautionary-motive, is determined by a function ($L_1$) of income ($Y$). He then says that $M_2$, as the savings corresponding to the speculative-motive, is determined by a function ($L_2$) of the interest rate ($r$). Thus, the total amount of savings in money ($M$) is jointly determined by the sum of the categories of savings: $M=M_1+M_2=L_1(Y)+L_2(r)$