What is the ruling on combining two known items whose price cannot be apportioned by parts in a single sale for a single price?
Chapter on Selling the Musarrah (Animal with milk retained in udder)
Al-Mughni
Book of Sales
Primary text
When the sale combines two known items that do not allow for price apportionment by parts (such as a free person and a slave, wine and vinegar, or a man's own slave and another person's slave), the sale is void concerning the item that cannot legally be sold. Regarding the other portion, there are two narrations. One view suggests that if one item is found to be unsaleable (like a free person), the buyer may retain the other item and is due a refund equivalent to the found item's value from the price paid. The stronger opinion is that the entire contract is void in this category, similar to the ruling regarding the two previous categories where ambiguity or mixing of lawful and unlawful occurs. This is argued because the price becomes indeterminate as it must be determined by apportionment based on value, which is presently unknown, resembling selling an item for its weight or its share of capital.
Supporting text
Malik voids the contract entirely unless the sale involves the seller's property and another's property, in which case the sale is valid for the seller's portion and contingent upon permission for the rest. Abu Hanifa agrees, stating if one item is undeniably unsaleable (like a free person or wine), the contract is void for both; otherwise, if it is contingent (like jointly owned property), it is valid for what the seller owns.