The separate excitation of the dynamo corresponds with the independently determined investment in the economic model, and the total excitation with i… - Arnold Tustin

When beliefs need some modification, We make it with much trepidation, For our world is then new, And things seem all askew, 'til we're used to the new formulation.

Once a full-employment policy has been adopted... the economic ’system’ just on that account is significantly different. Its equilibrium position has been shifted to a rising curve of trend close to and following the employment ceiling. The conditions of stability about this new level are radically different because the region of operation is now within the less flexible and sharply non-linear range of employment saturation

The writer, who as an engineer has spent most of his life in factories, is inclined to look at the basis for investment from a technological point of view... Consider … the class of industrial investments only... The situation is one of entrepreneurs and boards of directors considering, from time to time, various ’possibilities of investment’, such as extra lathes or looms, an extension to a factory, a venture in some completely new product, and so on. It is helpful to think of these ’opportunities for investment’ as existing, in a given situation, in great number and variety, whether they are at that moment under active consideration or not. When any such possibility is considered it is assessed in respect of ’expected profitability’. One may conveniently think of all possibilities of investment as ’quanta’ that can be placed in a schedule of small ranges of expected profitability according to these assessments. The placement of a given ’opportunity for investment’ on this schedule has some ’margin of uncertainty’ (a curious analogy with the case of the quanta of physics).