We shall talk as if the objective of internal balance were simply that of maintaining a level of total demand for all the country’s products sufficie… - James Meade

He was lucky enough to rub shoulders with a fellow student, Mr. W T. Newlyn, now lecturing on money at the University of Leeds, who was less of an engineer but more of a monetary theorist than himself. Together they discussed how monetary theory could be represented by an hydraulic model.

By a ‘spontaneous disturbance’ we shall mean any change in the underlying conditions, the cause of which we are prepared to take for granted and do not wish to examine, but the effect of which on the domestic and external position of our two countries we wish to examine. By a ‘policy’ change we shall mean a change which the State or some public authority brings about as a result of a definite decision of State policy in order to achieve some given end of general economic policy and in particular to offset some of the effects of a ‘spontaneous disturbance’. Finally, by an ‘induced’ change is meant a change in some quantity which occurs on purely commercial principles because of the repercussions of some previous ‘spontaneous’ or ‘policy’ change.

Now there are two ways in which the authorities of a particular country may combine the use of financial policy and of price adjustment. (i) First, financial policy may be used for the preservation of internal balance and price adjustment for the preservation of external balance. (ii) Second, financial policy may be used for the preservation of external balance and price adjustment for the preservation of internal balance. On either of these principles the authorities of any one country can set about the simultaneous preservation of internal and external balance.