Now, turning from the consideration of the particular instance, which we shall find reason to believe is peculiarly unfortunate when we deal with the statistics of the cotton industry, it must be observed that economic theory makes dead against this _à priori_ optimism. Ignoring, for the sake of convenience, the not improbable result that an economy of production may, at any rate for a time, swell profits instead of reducing prices, it will be evident that the whole value of the argument turns upon the effect of a fall of price in stimulating increased consumption. Now the problem, how far a given fall in price will force increased consumption, we have found in our discussion of monopoly prices to involve extremely intricate knowledge of the special circumstances of each case, and refined calculations of human motives. Everything depends upon "elasticity of demand," and we are certainly not justified in assuming that in a particular industry a given fall of prices due to machine-production will stimulate so large an increase of consumption that employment will be given to as many, or more persons than were formerly employed. On the contrary, if we apply a similarly graduated fall of prices to two different classes of goods, we shall observe a widely different effect in the stimulation of consumption. A reduction of fifty per cent. in the price of one class of manufactured goods may treble or quadruple the consumption, while the same reduction in another class may increase the consumption by only twenty per cent. In the former case it is probable that the ultimate effect of the machinery which has produced the fall in expenses of production and in prices will be a considerable increase in the aggregate demand for labour, while in the latter case there will be a net displacement. It is therefore impossible to argue _Ã priori_ that the ultimate effect of a particular introduction of machinery must be an increased demand for labour, and that the labour displaced by the machinery will be directly or indirectly absorbed in forwarding the increased production caused by machinery. It is alleged that the use of steam-hammers has displaced nine of the ten men formerly required, that with modern machinery one man can make as many bottles as six men made formerly, that in the boot and shoe trade one man can do the work five used to do, that "in the manufacture of agricultural implements 600 men now do the work which fifteen or twenty years ago required 2145, thus displacing 1515," and so forth.[176] Now in some of these cases we shall find that the fall of prices following such displacements has led to so large an increase of demand that more persons are directly engaged in these industries than before; in other cases this is not the case. The following quotation from a speech made at the Industrial Remuneration Conference in 1885 will present the most effective criticism upon Professor Leone Levi's position:--