(p.74) Thus, when a field is ploughed and sown, besides the science and the labour employed in this operation, besides the pre-created values brought into use, the values, for instance, of the plough, the harrow, the process of production, there is a process performed by the soil, which nevertheless concurs in the creation of the new product that will be acquired at the season of harvest. This process I call the productive  agency of natural agents.

(p.76) The man who discovered the property of fire to soften metals, was not the creator of this utility this process adds to smelted ore. That utility results from the physical action of fire, in concurrence, it is true with the labour and capital of those who employ the process. But are there no processes that mankind owes the knowledge to pure accident? Or that are so self-evident, as to have required no skill to discover? When a tree, a natural product, is felled, is society put into possession of no greater produce than of the mere labour of the woodman?...

(p.87) Machines cannot be constructed without considerable labout. Which gives occupations to the hands they throw out of employ. For instance the supply of a city with water by conduits gives increased occupation to carpenters, masons, smith, paviours & c. in the construction of the works, the laying down the main and branch pipes, &c, &c

(p.103) There is a further branch of commerce, called trade of speculation which consists in the purchase of goods at one time, to be resold in the same place and condition at another time, when they are expected to be dearer. Even this trade is productive: its utility consists in the employment of capital, warehouse, care in the preservation, in short, human industry in the withdrawing from circulation a commodity depressed in value by temporary superabundance, and thereby reduced in price below the charges of production, so as to discourage its production, with the design and purpose of restoring it to...

(p.140) In a community, city, province, or nation, that produces abundantly, and adds every moment to the sum of its products, almost all the branches of commerce, manufacture, and generally of industry, there is always a large quantity of products in the market, ready to bid for new productive services. And vice versa, whenever, by reason of the bludners of the nation or its government, production is stationary, or does not keep pace with consumption, the demand gradually declines, the value of the product is less than the charges of its production; no productive exertion is properly rewarded; profits and wages...

(p.217) In a society ever so little advanced in civilisation, no single individual produces all that is necessary to satisfy his own wants; and it is rarely that an individual, by his single exertion, creates even any single product; but even if he docs, his wants are not limited to that single article; they are numerous and various, and he must, therefore, procure all other objects of his personal consumption, by exchanging the overplus of the single product he himself creates beyond his own wants, for such other products as he stand in need of. And, by the way, it is...

(p.245) The value of labour is affected materially by its quality. The labour of a strong and intelligent person is worth much more than that of a weak and ignorant one. Again, labour is more valuable in a thriving community, where there is a lively demand for it, than in a country overloaded with population. In the United States, the daily wage of an artificer amounts in silver to three times as much value in France. Are we to infer, that silver has then but 1/3 of its value in France? The artificer is there better fed, better clothed, and better...

(p.65) No human being has the faculty of originally creating matter, which is more than nature itself can do but anyone may avail himself of the agents offered him by nature, to invest matter with utility. In fact, industry is nothing more or less than the human employment of natural agents; the most perfect product of labour, the one that derives nearly its whole value from its workmanship is probably the result of the action of steel, a natural product upon some substance or other, likewise a natural product.