Sublime

As stated there (ibid.:11), the obligation to return the article or the money applies only when both parties are Jewish. Although it is forbidden to deceive a gentile regarding the value of merchandise, it is not forbidden to take advantage of an error the gentile makes on his own.

As stated in subsection 11, the prohibition refers only to a fellow Jew. There are, however, prohibitions against deceiving a gentile. See

forbidden to deceive a gentile even with regard to a matter that will not cause him a loss, e.g., to sell him meat from an animal that

It is forbidden to mix a small amount of [inferior] produce into a large amount of superior produce so that [the inferior produce] will not be recognized95 and [then] sell the entire quantity under the presumption that it is [all] of higher quality.96

who speaks most disparagingly of one who seeks to profit by deceiving gentiles. He concludes stating that Divine Providence will not bless such a person’s endeavors. Even if he may profit in the short term, his money will not be graced with blessing and ultimately, will be lost.

It is forbidden to take unfair advantage1 of another person,2 neither when purchasing from him — to purchase at a lower price than [the article’s]3 worth, even a p’rutah’s4 worth5 — nor when selling to him — to sell it at even a p’rutah more than its worth. If one takes unfair advantage, he violates a negative commandment,6 as it is written:7 “When

He should not, however, include the fee for his efforts as part of the merchandise’s purchase price (for in people’s minds, this is included in the profit margin, which [the seller] receives according to their negotiations. It should not be included as part of the price of the merchandise since he did not spend money on this; [he only expended effo