however wealth may be defined, is obviously of the greatest use in explaining the causes of the increase of wealth. The only essential objection to it is, that it seems to underrate the importance of all other kinds of labour—at least the term unproductive labour, used by Adam Smith to express all other kinds of labour, has been frequently so interpreted, and has formed in consequence the great objection to his classification. To remove this objection to a classification in other respects sufficiently correct for practical purposes, and beyond comparison more useful in explaining the causes of the wealth of nations, than any other which has hitherto been suggested, it might be desirable to substitute the term personal services for unproductive labour.
Labour may then be distinguished into two kinds, productive labour, and personal services, meaning by productive labour that labour which is so directly productive of material wealth as to be capable of estimation in the quantity or value of the object produced, which object is capable of being transferred without the presence of the producer; and meaning by personal services that kind of labour or industry, which however highly useful and important some of it may be, and however much it may conduce indirectly to the production and security of material wealth, does not realize itself on any object which can be valued and transferred without the presence of the person performing such service, and cannot therefore be made to enter into an estimate of national wealth.
This, though differing in name, is essentially the doctrine of Adam Smith. It has been controverted by two opposite parties, one of which has imputed to him an incorrect and unphilosophical extension of the term productive to objects which it ought not to include, and the other has accused him of a similar want of precision, for attempting to establish a distinction between two different sorts of labour where no distinction is to be found.
