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).