When there is an agrarian law, and the lands are equally divided, the country can be very populous even though there are few arts, because each citizen obtains by working his land precisely enough food, and all the citizens together consume all the fruits of the earth : so it was in some ancient republics.
But in our states today, where parcels of land are so unequally distributed, more fruits of the earth are produced than those who cultivate them can consume ; and if the arts are neglected, and agriculture is the only industry, the country cannot be populous. Since those who cultivate or have others cultivate the land have leftover production, nothing forces them to work the following year ; the produce would not be consumed by idle men, for idle men would not be able to afford them. It is therefore necessary for the arts to become established so the produce will be consumed by the farm workers and artisans. In a word, in these states there need to be many who raise more than they require ; for that, they must be given the desire to have the surplus ; but it is only artisans who give it.
These machines designed to simplify art are not always useful. If a piece of work is at a modest price, one that equally suits the buyer and the worker who made it, machines which will simplify its production, in other words which will reduce the number of workers, would be pernicious ; and if water mills were not set up everywhere, I would not believe them as useful as people say, because they have stilled an infinite number of hands, deprived many men of access to water, and cost the fertility of many fields.