Is knowledge of the exact measure required when the consideration in an *ijarah* is known by sight, such as a pile of grain?
General Chapter
Al-Mughni
Book of Leasing
Primary text
When the consideration in the *ijarah* contract is known by sight but its measure is unknown (e.g., a pile (*sabra*)), the stronger position permits the contract. This is because the usufruct (*manfa'ah*) in *ijarah* is treated as property (*a'yan*) since it relates to an existing item, unlike *salam* which involves a non-existent item.
Supporting text
A dissenting view holds that the contract is invalid because if the item is destroyed, the exact measure of return becomes unknown, thus requiring the measure to be known like the consideration in a *salam* contract.