Having already sufficiently considered the general principles of this subject, let us now go into the practical part thereof; the one is a liberal employment for the mind, the other necessary. These things are useful in the management of one's affairs; to be skilful in the nature of cattle, which are most profitable, and where, and how; as for instance, what advantage will arise from keeping horses, or oxen, or sheep, or any other live stock; it is also necessary to be acquainted with the comparative value of these things, and which of them in particular places are worth most; for some do better in one place, some in another. Agriculture also should be understood, and the management of arable grounds and orchards; and also the care of bees, and fish, and birds, from whence any profit may arise; these are the first and most proper parts of domestic management.

With respect to gaining money by exchange, the principal method of doing this is by merchandise, which is carried on in three different ways, either by sending the commodity for sale by sea or by land, or else selling it on the place where it grows; and these differ from each other in this, that the one is more profitable, the other safer. The second method is by usury. The third by receiving wages for work done, and this either by being employed in some mean art, or else in mere bodily labour. There is also a third species of improving a fortune, that is something between this and the first; for it partly depends upon nature, partly upon exchange; the subject of which is, things that are immediately from the earth, or their produce, which, though they bear no fruit, are yet useful, such as selling of timber and the whole art of metallurgy, which includes many different species, for there are various sorts of things dug out of the earth.

These we have now mentioned in general, but to enter into particulars concerning each of them, though it might be useful to the artist, would be tiresome to dwell on. Now of all the works of art, those are the most excellent wherein chance has the least to do, and those are the meanest which deprave the body, those the most servile in which bodily strength alone is chiefly wanted, those most illiberal which require least skill; but as there are books written on these subjects by some persons, as by Chares the Panian, and Apollodorus the Lemnian, upon husbandry and planting; and by others on other matters, [1259b] let those who have occasion consult them thereon; besides, every person should collect together whatsoever he hears occasionally mentioned, by means of which many of those who aimed at making a fortune have succeeded in their intentions; for all these are useful to those who make a point of getting money, as in the contrivance of Thales the Milesian (which was certainly a gainful one, but as it was his it was attributed to his wisdom, though the method he used was a general one, and would universally succeed), when they reviled him for his poverty, as if the study of philosophy was useless: for they say that he, perceiving by his skill in astrology that there would be great plenty of olives that year, while it was yet winter, having got a little money, he gave earnest for all the oil works that were in Miletus and Chios, which he hired at a low price, there being no one to bid against him; but when the season came for making oil, many persons wanting them, he all at once let them upon what terms he pleased; and raising a large sum of money by that means, convinced them that it was easy for philosophers to be rich if they chose it, but that that was not what they aimed at; in this manner is Thales said to have shown his wisdom. It indeed is, as we have said, generally gainful for a person to contrive to make a monopoly of anything; for which reason some cities also take this method when they want money, and monopolise their commodities. There was a certain person in Sicily who laid out a sum of money which was deposited in his hand in buying up all the iron from the iron merchants; so that when the dealers came from the markets to purchase, there was no one had any to sell but himself; and though he put no great advance upon it, yet by laying out fifty talents he made an hundred. When Dionysius heard this he permitted him to take his money with him, but forbid him to continue any longer in Sicily, as being one who contrived means for getting money inconsistent with his affairs. This man's view and Thales's was exactly the same; both of them contrived to procure a monopoly for themselves: it is useful also for politicians to understand these things, for many states want to raise money and by such means, as well as private families, nay more so; for which reason some persons who are employed in the management of public affairs confine themselves to this province only.