"All labour is directed towards producing some effect. For though some exertions are taken merely for their own sake, as when a game is played for amusement, they are not counted as labour. We may define labour as any exertion of mind or body undergone partly or wholly with a view to some good other than the pleasure derived directly from the work. And if we had to make a fresh start it would be best to regard all labour as productive except that which failed to promote the aim towards which it was directed, and so produced no utility. But in all the many changes which the meaning of the word "productive" has undergone, it has had special reference to stored-up wealth, to the comparative neglect and sometimes even to the exclusion of immediate and transitory enjoyment; and an almost unbroken tradition compels us to regard the central notion of the word as relating to the provision for the wants of the future rather than those of the present. It is true that all wholesome enjoyments, whether luxurious or not, are legitimate ends of action both public and private; and it is true that the enjoyment of luxuries affords an incentive to exertion, and promotes progress in many ways. But if the efficiency and energy of industry are the same, the true interest of a country is generally advanced by the subordination of the desire for transient luxuries to the attainment of those more solid and lasting resources which will assist industry in its future work, and will in various ways tend to make life larger. This general idea has been in solution, as it were, in all stages of economic theory; and has been precipitated by different writers into various hard and fast distinctions by which certain trades have been marked off as productive and certain others as unproductive."