Key Arguments

• He summarizes that the ‘great increase in the quantity of work’ made possible by the division of labour ‘is owing to three different circumstances’, which he then enumerates systematically: increased dexterity, saving of time, and invention of machines.
• First, ‘the improvement of the dexterity of the workmen, necessarily increases the quantity of the work he can perform’, and division of labour ‘by reducing every man’s business to some one simple operation’ and making it ‘the sole employment of his life’ ‘necessarily increases very much the dexterity of the workman’, directly raising output per worker.
• To show the magnitude of this effect, he compares three nail‑making cases: a common smith unused to nails can barely make ‘two or three hundred nails in a day’ and ‘very bad ones’; a smith accustomed to nails but not a specialist can make at most ‘eight hundred or a thousand nails in a day’; boys under twenty who have never done anything but make nails can each make ‘upwards of two thousand three hundred nails in a day’.
• He notes that nail‑making ‘is by no means one of the simplest operations’ because the same person must blow the bellows, manage the fire, heat the iron, forge every part, and change tools, implying that in even more subdivided operations (like pins or metal buttons) dexterity, and thus productivity, will be greater still.
• Second, he argues that the advantage from saving time lost in passing from one kind of work to another ‘is much greater than we should at first view be apt to imagine it’, because when work is done in different places with different tools, or when one man alternates between trades, considerable time is lost in movement and adjustment.
• He illustrates this with the ‘country weaver, who cultivates a small farm’, who must lose much time going ‘from his loom to the field, and from the field to his loom’, and notes that even when multiple trades are in the same workhouse, time is lost when changing tasks.
• He highlights psychological as well as physical costs: a man ‘commonly saunters a little in turning his hand from one sort of employment to another’; when he begins new work he is ‘seldom very keen and hearty’, and for some time ‘rather trifles than applies to good purpose’.
• The ‘habit of sauntering, and of indolent careless application’ that is ‘necessarily’ acquired by a country workman frequently changing work and tools ‘every half hour’ and applying his hand ‘in twenty different ways almost every day’ makes him ‘almost always slothful and lazy, and incapable of any vigorous application’, which, even apart from inferior dexterity, ‘must always reduce considerably the quantity of work which he is capable of performing’.
• Third, he says that ‘everybody must be sensible’ how much labour is ‘facilitated and abridged by the application of proper machinery’ and that ‘one man’ can be enabled ‘to do the work of many’, pointing to machinery as a major multiplier of productivity.
• He then advances the further claim that ‘the invention of all those machines’ by which labour is facilitated and abridged ‘seems to have been originally owing to the division of labour’, because when a man’s whole attention is directed to a single simple object, he is more likely to discover easier and readier methods for performing that task.
• He notes that ‘a great part of the machines’ used in highly subdivided manufactures ‘were originally the invention of common workmen’ whose thoughts were naturally turned to improving their own very simple operations, and that visitors to such manufactures are often shown ‘very pretty machines’ invented by such workers to ‘facilitate and quicken their own particular part of the work’.

Source Quotes

In Poland there are said to be scarce any manufactures of any kind, a few of those coarser household manufactures excepted, without which no country can well subsist. This great increase in the quantity of work, which, in consequence of the division of labour, the same number of people are capable of performing, is owing to three different circumstances; first, to the increase of dexterity in every particular workman; secondly, to the saving of the time which is commonly lost in passing from one species of work to another; and, lastly, to the invention of a great number of machines which facilitate and abridge labour, and enable one man to do the work of many. First, the improvement of the dexterity of the workmen, necessarily increases the quantity of the work he can perform; and the division of labour, by reducing every man’s business to some one simple operation, and by making this operation the sole employment of his life, necessarily increases very much the dexterity of the workman.

This great increase in the quantity of work, which, in consequence of the division of labour, the same number of people are capable of performing, is owing to three different circumstances; first, to the increase of dexterity in every particular workman; secondly, to the saving of the time which is commonly lost in passing from one species of work to another; and, lastly, to the invention of a great number of machines which facilitate and abridge labour, and enable one man to do the work of many. First, the improvement of the dexterity of the workmen, necessarily increases the quantity of the work he can perform; and the division of labour, by reducing every man’s business to some one simple operation, and by making this operation the sole employment of his life, necessarily increases very much the dexterity of the workman. A common smith, who, though accustomed to handle the hammer, has never been used to make nails, if, upon some particular occasion, he is obliged to attempt it, will scarce, I am assured, be able to make above two or three hundred nails in a day, and those, too, very bad ones.

When he first begins the new work, he is seldom very keen and hearty; his mind, as they say, does not go to it, and for some time he rather trifles than applies to good purpose. The habit of sauntering, and of indolent careless application, which is naturally, or rather necessarily, acquired by every country workman who is obliged to change his work and his tools every half hour, and to apply his hand in twenty different ways almost every day of his life, renders him almost always slothful and lazy, and incapable of any vigorous application, even on the most pressing occasions. Independent, therefore, of his deficiency in point of dexterity, this cause alone must always reduce considerably the quantity of work which he is capable of performing.

It is naturally to be expected, therefore, that some one or other of those who are employed in each particular branch of labour should soon find out easier and readier methods of performing their own particular work, whenever the nature of it admits of such improvement. A great part of the machines made use of in those manufactures in which labour is most subdivided, were originally the invention of common workmen, who, being each of them employed in some very simple operation, naturally turned their thoughts towards finding out easier and readier methods of performing it. Whoever has been much accustomed to visit such manufactures, must frequently have been shewn very pretty machines, which were the inventions of such workmen, in order to facilitate and quicken their own particular part of the work.

Key Concepts

• This great increase in the quantity of work, which, in consequence of the division of labour, the same number of people are capable of performing, is owing to three different circumstances;
• first, to the increase of dexterity in every particular workman; secondly, to the saving of the time which is commonly lost in passing from one species of work to another; and, lastly, to the invention of a great number of machines which facilitate and abridge labour, and enable one man to do the work of many.
• the division of labour, by reducing every man’s business to some one simple operation, and by making this operation the sole employment of his life, necessarily increases very much the dexterity of the workman.
• The habit of sauntering, and of indolent careless application, which is naturally, or rather necessarily, acquired by every country workman who is obliged to change his work and his tools every half hour, and to apply his hand in twenty different ways almost every day of his life, renders him almost always slothful and lazy, and incapable of any vigorous application, even on the most pressing occasions.
• a great part of the machines made use of in those manufactures in which labour is most subdivided, were originally the invention of common workmen, who, being each of them employed in some very simple operation, naturally turned their thoughts towards finding out easier and readier methods of performing it.

Context

Later in Chapter I, Smith systematically analyzes why division of labour raises productivity, breaking the causal mechanism into three parts—dexterity, time‑saving, and machinery—and supporting each with concrete examples and psychological observations about workers.