6. There has certainly been an increase of wealth in our own country in recent years, but it has not necessarily been accompanied with an increased rate of profits (V, cf. XX).
In Letters XV to XXI the following are the chief propositions:—
1. Restrictions on the importation of corn by keeping up the price of necessaries have a tendency to lower profits (XV), unless, indeed, they are followed by a great reduction of capital (XVI, XVII).
2. The only cause of permanently high or low profits is the facility of procuring necessaries, for on that mainly depends the rate of wages (XVI, XVIII, XIX, XX, XXI, cf. V, and for qualification LXXIX, LXXX).
3. Other causes, such as bad harvests, new taxation, changes in demand, or excessive accumulation, are merely temporary (XX, XXI, cf. Ricardo's Pol. Econ. and Tax., ch. vi. 'On Profits').
4. Improvements in agriculture or machinery by increasing productiveness permanently increase profits (XX, cf. V and XXIII).
To these may be added—
5. Consumption and accumulation equally promote demand, and are both of them ineradicable tendencies of our nature, the one adding to our enjoyments, the other to our power (XIX).
6. Accumulation increases not only production, but consumption (XXI).
7. It is worth while to establish the truth of a principle, even if we cannot establish its utility (XXI).