equally applicable in all times and places; and that, having obtained them, we need not trouble ourselves any further with inductions. Hence it follows that we can at once get from the abstract 'man' to the industrial order. We may, it would seem, abstract from history in general. This corresponds to the postulate explicitly stated by M'Culloch. 'A state,' he tells us, 'is nothing more than an aggregate of individuals': men, that is, who 'inhabit a certain tract of country.'[362] He infers that 'whatever is most advantageous to them' (the individuals) 'is most advantageous to the state.' Self-interest, therefore, the individual's desire of adding to his 'fortune,' is the mainspring or _causa causans_ of all improvement.[363] This is, of course, part of the familiar system, which applies equally in ethics and politics. M'Culloch is simply generalising Adam Smith's congenial doctrine that statesmen are guilty of absurd presumption when they try to interfere with a man's management of his own property.[364] This theory, again, is expressed by the familiar maxim _pas trop gouverner_, which is common to the whole school, and often accepted explicitly.[365] It will be quite enough to notice one or two characteristic results. The most important concern the relation between the labourer and the capitalist. Malthus gives the starting-point. Torrens, for example, says that the 'real wages of labour have a constant tendency to settle down' to the amount rendered necessary by 'custom and climate' in order to keep up his numbers.[366] Mill observes in his terse way that the capitalist in the present state of society 'is as much the owner of the labour' as the manufacturer who operates with slaves. The only 'difference is in the mode of purchasing.'[367] One buys a man's whole labour; the other his labour for a day. The rate of wages can therefore be raised, like the price of slaves, only by limiting the supply. Hence the 'grand practical problem is to find the means of limiting the number of births.'[368] M'Culloch is equally clear, and infers that every scheme 'not bottomed on' the principle of proportioning labour to capital must be 'completely nugatory and ineffectual.'[369]