“In a civilised society,” he reminds his class, “though there is a division of labour, there is no equal division, for there are a good many who work none at all. The division of opulence is not according to the work. The opulence of the merchant is greater than that of all his clerks, though he works less; and they again have six times more than an equal number of artisans who are more employed. The artisan who works at his ease within-doors has far more than the poor labourer who trudges up and down without intermission. Thus, he who, as it were, bears the burden of society, has the fewest advantages.” Division of labour multiplies the product of labour and so creates opulence. He takes a pin manufactory as an illustration. If one man made all the parts of a pin it would take him a year, and the pin would cost at least six pounds. By dividing the process of manufacture into eighteen operations, each man employed can make 2000 pins a day. When labour is thus divided, a much larger surplus is left over and above the labourer’s maintenance, and of this surplus the labourer will get a share. “The commodity becomes far cheaper and the labour dearer.” The less the labour that can procure abundance, the greater the opulence of society. But coin is not a safe criterion of wages. Twopence in China will buy more than five shillings in the sugar colonies. By dividing labour you increase dexterity. A boy nailmaker will easily make 2000 good nails while a country smith unaccustomed to the job is making 400 bad ones. You also save time; for time is always lost in going from one kind of work to another. “When a person has been reading, he must rest a little while before he begin to write”; and a country weaver with a small farm will saunter as he goes from the loom to the plough. By fixing each man to an operation the product is sure to be increased. Again, the quantity of work done is much augmented by the invention of machinery. Two men and three horses can do more with a plough than twenty men with spades. The miller and his servant will do more with the water-mill than a dozen men with the hand-mill. Horse-power and water-power had been brought to the assistance of man by philosophic invention; and even fire had been called in to aid him by the mechanical and chemical discoverers. The lecturer was doubtless thinking of his colleague Joseph Black, and of James Watt, who was at this time working within the precincts of Glasgow College, and was just developing what Smith calls “the philosopher’s invention of the fire machine.”