§ VI. On the Obligations of the Buyer

Three obligations of the buyer are given, of which one is principal; while the two remaining are less frequent and accidental.

A. On the principal obligation of the buyer.

993. • The principal obligation of the buyer is: that he buy the vendible thing at a just price and faithfully pay it in the due place and time.

B. On the twofold obligation of the buyer, less frequent and accidental.

994. • The first obligation, less frequent and accidental, is the obligation (whether expressly, or at least tacitly, i.e. by increasing the price up to the vulgar lowest) of manifesting to a simple and ignorant seller the goodness of the merchandise which he wishes to sell more cheaply, not knowing its value; for otherwise the buyer would not buy at the just price, i.e. not at so much as the thing is worth in common estimation. Nor is the buyer to be excused when in such a case he asks the ignorant seller to condone it if perhaps the thing is worth more; for a donation of this kind would be invalid, as founded in ignorance. Besides, to understand rightly the aforesaid obligation of the buyer, observe:

a) That obligation probably cannot be extended so far as that the buyer would have to make the seller, even one questioning him, more certain of the highest value of the thing which is unknown; for I am able with St. Alphonsus¹ to apprehend no injustice in the buyer who justly buys by paying the lowest price, and besides does not positively deceive the seller or compel him to sell. - But that the seller is ignorant that this price is the lowest is accidental and must be imputed to him.

b) The same obligation does not comprehend the case in which there is question of a thing which in the common estimation of the place is held as cheap, although the buyer by private knowledge recognizes its greater value; nor the case in which both buyer and seller, laboring under ignorance, in good faith enter a quasi-aleatory contract, committing themselves to fortune.

The second obligation, less frequent and accidental, is the obligation of the buyer to manifest candidly and totally to the seller the vices of the price, if any perhaps exist here and now, for example if the buyer pays coins or notes for the price, which here and now are of doubtful or litigated value. But by saying: here and now, we sufficiently suggest that an obligation of this kind does not touch the case in which the discussion is about a price which here and now is best, but which the buyer privately knows is soon to be diminished on account of some extrinsic circumstance in the future. See concerning this case the resolution handed down previously in n. 973.