“If the established division is adhered to, and all that is produced is to be divided into rent, profit, and wages,—and certainly that appears to be the most convenient classification,—and if wages and profit are to be considered as the rewards of peculiar sacrifices, ... it is clear that under the term ‘rent’ must be included all that is obtained without any sacrifice; or, which is the same thing, beyond the remuneration for that sacrifice; all that nature or fortune bestows either without any exertion on the part of the recipient, or in addition to the average remuneration for the exercise of industry or the employment of capital.”[147] Accordingly, rent includes not only the return to land, in the widest economic sense of this term, but also the return to secret processes of production, and to talents or extraordinary personal abilities.[148] This necessitates the very curious use of the words “natural agents” to include exclusive knowledge of, or right to, an advanced process, and talents or unusual faculties: “The mere knowledge of the operations of nature, as long as the use of that knowledge can be confined either by secrecy or law, creates a revenue to its possessor analogous to the rent of land ... so precisely resembling the rent of land, that it often receives the same name,” (and it must be called rent). The salary, wages, or remuneration of the laborer may really be composed of wages, rent, and profits: “Is then the extraordinary remuneration of the labourers, which is assisted by extraordinary talents, to be termed Rent or Wages? It originates in the bounty of nature; so far it seems to be rent. It is to be obtained only on the condition of undergoing labour; so far it seems to be wages. It might be termed ... rent which can be received only by a labourer, or wages which can be received only by the proprietor of a natural agent. But as it is clearly a surplus, the labour having been previously paid for by average wages, and that surplus the spontaneous gift of nature, we have thought it most convenient to term it rent.”[149] 6. Does this rent, the surplus of value above reward for true cost of production, “enter into price?” Senior does not use these words or discuss this question directly, but, although he follows Ricardo precisely in explaining rent as a differential return and defends the doctrine vigorously against Say’s attacks, he assumes nevertheless, contrary to Ricardo, that rent does “enter into price” in the sense of constituting a source of permanent disproportionality of value to subjective cost of production. As was intimated some pages back, the state of free competition, as understood by Senior, is highly ideal, postulating not only the ordinary condition of ideal mobility of capital and labor, but also the use of none but free natural agents: