to the sale of assets and argues, “Just as assets can be sold only when they exist, so too can usufructs”—which is what his argument really amounts to—then this analogy is utterly unsound. A condition of valid analogy is that the ruling governing the original case must be applicable to the new case. Here, however, that is impossible, because usufructs cannot be made the subject of a contract while they exist. It is therefore inconceivable that usufructs should be sold while they exist in the same way that assets are sold while they exist.

The Lawgiver has instructed people to postpone contracts concerning assets not yet created until they have been created. Thus, He prohibited sales of future years’ crops, the sale known as habal al-habalah, sales of fruit before its ripeness becomes apparent, and sales of grain before it hardens. He also prohibited sales of al-madāmīn and al-malāqīh, and al-majr, meaning what is carried in the womb. All these are prohibitions against selling animals before they have been created, or grain and fruit before they have been created; He commanded that their sale be postponed until they have been created.

This distinction—prohibiting its sale in one circumstance and leasing it in another—cannot apply to usufructs, since they can be sold only in this manner. Thus, the ruling governing the original case no longer matches that governing the new case. The only remaining argument would be to say, “Then I draw an analogy between it and the sale of nonexistent assets.”

The reply is: “There are two things here. One can be sold both when it exists and when it does not, but the Lawgiver has prohibited its sale unless it exists. The other can be sold only while it does not exist. Since the Lawgiver prohibited selling the former while it does not exist, it is necessary, if