בעזהי"ת, סיון, תשע"ט
From the members of the Kollel Aliyos Shlomo
A TEST QUESTION ON MASECHES BAVA METZIA,
In the איסור אונאה the Torah forbids us to overcharge or to underpay when selling or making a purchase. Rava paskens that a deviation of less than one-sixth of the price has no consequences. That is, the sale stands and the amount of the deviation
does not have to be returned. The רא"ש (פ"ד סי' כ') in one explanation of this halacha, writes: It is normal in commerce that a purchaser will have particular, individualistic reasons to buy an an inflated price or that a seller will sell at a deflated price. Therefore, any variation of up to one-sixth from the accepted price is included in the "דמי מקח" and does not enter into the realm of underpayment/overcharging at all.
The expression "דמי מקח" used by the רא"ש can be understood in two ways: 1) It means value. That is, the value of any given merchandise is a range of from one-sixth below to one-sixth above the market price.
Or 2) It means "fair price". That is, although the value of any given item is the market price, not more and not less, however, "fair price" and "value" are two separate things. Idiosyncratic deviations will affect the "fair price" but not the "true value" of the merchandise. The fair price is a range, the value is not.
The first פשט is simpler and more straightforward, and therefore preferred. However, the גמרא (נב:) forces us to abandon the first פשט and to conclude like the second פשט. Explain how this is so.
The answer will appear in about a week, בעזהי"ת.