Is a contract for sale or purchase valid when executed by a blind person?
Chapter on Selling the Musarrah (Animal with milk retained in udder)
Al-Mughni
Book of Sales
Primary text
The sale and purchase contract executed by a blind person is valid if the object of the sale can be identified through senses like tasting if edible or smelling if aromatic. If identification through these means is not possible, the sale remains permissible, similar to a sighted person's transaction, but the blind person retains the option to rescind (khiyar al-khalaf) if the object's description does not match reality upon later acquaintance. This view is held by Malik and Abu Hanifa. Abu Hanifa specifically grants the option to rescind until the object is known either through sensation, taste, or description. Ubayd Allah ibn al-Hasan affirmed validity if the blind person instructs another to inspect the item, which then binds them.
Supporting text
Al-Shafi'i holds that the transaction is invalid unless it falls under the exceptions where unknown items are permissible, or if the blind person had seen the item while sighted and purchased it before a time elapsed where the item could change. This is because the item's characteristic is unknown to the contracting party, similar to selling eggs inside a hen or pits inside a date.