(a) There is an indicated condition when the buyer inquires whether there are defects in the article, having the intention to take nothing that has any considerable defect. In such a case if the seller conceals even an accidental defect (i.e., one that makes the article less suitable for the buyer), the contract is null on account of lack of consent, or at least, as others think, it is rescindable on account of the fraud practised. But if a defect is inconsiderable, the contract, unless it is expressly stipulated to the contrary, is good and lawful, for there is hardly anything that has not some small defects.
(b) There is an implied condition when the buyer makes no inquiry, but there is a substantial defect (i.e., one that makes the article dangerous or unsuitable for the purchaser), and this defect is hidden, either because it is of a kind that would escape most persons, or because the purchaser is inexperienced or unable to perceive it for himself. Since every person who buys intends to get something useful, there is no consent and the contract is invalid, if one is given something harmful (e.g., corrupted or poisonous food instead of good food), or something entirely useless to him either for service or for sale (e.g., a lame horse instead of a sound horse for one who deals in race-horses).
2133. Circumstances in Which Defects Need Not Be Revealed.—Fairness of price being supposed, the seller is not unjust in not calling attention to defects in the thing he sells, if the buyer does not ask about defects and there is no implied condition that the seller should volunteer the information. This happens as follows:
(a) if the defect is hidden, but only accidental, there is no condition that the seller shall point out the defect, for the understanding is only that the buyer shall receive something serviceable at a fair return for his money, Nevertheless, most merchants wish to please the public and will take back or exchange an article that is not satisfactory;
(b) if the defect is open, but accidental, there is no condition that the seller shall instruct the buyer about things that the latter can and should observe for himself; for it is supposed that the buyer will exercise ordinary care and prudence in making purchases, nor is the seller paid for supplying this, nor for assisting the buyer to make good bargains. Thus, if a man were to buy a one-eyed horse, because he had not examined the horse, he should blame his own negligence, not the silence of the seller, for his bad bargain.
2134. Definition of Trading.—Trading (_negotiatio_) in the strict sense is the purchase of an object with the intention of selling it unchanged at a profit. If any one of the conditions mentioned in this definition are lacking, there is trading in a wide sense. (a) Thus, trading includes purchase, and hence he who sells the produce of his own farm or vineyard is not strictly a trader; (b) there must be an intention of reselling the thing bought, and hence there is trading only in a wide sense if one buys an article for one’s own use but, finding it unsuitable to that use, sells it to another person; (c) the object must be sold unchanged, that is, in the same form in which it was received, otherwise there is not strict negotiation, as when one buys colors and canvas and makes them into a picture; (d) the object must be sold at a higher price than was paid for it, and hence it is not trading in the strict sense to let a customer have an article for just what it has cost oneself.
2135. The Morality of Trading in the Strict Sense.—(a) In itself, trading has the appearance of evil, inasmuch as money-making may be an encouragement to avarice. But in reality profit as an end is morally indifferent, neither good nor bad, and all will depend on the ultimate reason for which one engages in business. He who makes the whole purpose of his existence the acquisition of gain is a materialist, but he who has some higher end, such as public benefit or private maintenance, is virtuous in his aims. (b) For clerics, trading is forbidden by Canon Law (Canon 142), and the reason is that clerics should be free from the distractions and dangers of commerce, so as to devote themselves entirely to their own spiritual duties (II Tim., ii. 4).
2136. Usury.—The sin of usury is committed in two ways.
(a) Usury in the strict sense is the taking of interest by reason of intrinsic title (i.e., on account of the use) for money or other fungible loaned on condition that it be restored in kind (_mutuum_). This is unjust since it exacts payment for that which is nonexistent, that is, for use, as a distinct value, of a fungible whose only value is in its use (see Aristotle, _Politics_, Bk. I, Ch. 10, 1258b 2-8; St. Thomas, Summa Theologica II-II, q. 78, a. 1). This was the opinion of most medieval theologians based on the fact that money was solely a medium of exchange. Interest was permitted, however, on the grounds of extrinsic titles, e.g., compensation for the expense of a transaction (_damnum emergens_), the loss of opportunity to make good bargains (_lucrum cessans_).
(b) Usury in the wide sense, which is all too common, is the taking of interest for a fungible loaned at _mutuum_, where there is an extrinsic title (e.g., the loss or inconvenience suffered by the lender) for the interest, but the rate charged is unjust, exceeding that fixed by law or that which is fair and reasonable (see Canon 1543). This is unjust when the lender takes more than his loan is worth; it is uncharitable when the lender does not demand more than the worth of his loan, but does exact what is due in a heartless manner. Examples of usury in the wide sense are the acts of loan sharks who take advantage of the distress of the poor to make them pay enormous interest for small loans, or who hold the debtor to the strict letter of the agreement at a great loss to him.