Kitab al-Buyu: Shortage, Surplus, Buyer Options and Price Allocation

1. Stated quantity versus actual quantity

The preceding section dealt with selling lots, measured grain, and per-unit prices. The present passage deals with a new problem: a specific quantity was promised, but subsequent measurement reveals a shortage or surplus.

A difference between 10 and 8, or between 10 and 12, does not always have one ruling. We must ask whether quantity identifies separate measurable portions, serves as a description of a single item, or has been assigned its own price for each unit.

That distinction governs proportional price, ownership of surplus, and the buyer's option to cancel.

2. Deficient heap: original ruling

ومن ابتاع صبرة طعام على أنها مائة قفيز بمائة درهم فوجدها أقل كان المشتري بالخيار
Translation: Whoever buys a heap of food described as 100 qafiz for 100 dirhams and finds it to contain less has an option.

Sabrah means a grain heap; qafiz is a historical unit of capacity. The agreement here expressly specifies 100 qafiz, not merely an unidentified amount of grain.

A shortfall means part of the contracted quantity is absent. The buyer therefore receives an option rather than being automatically compelled to keep whatever happens to be present.

3. Shortage: proportionate acceptance

إن شاء أخذ الموجود بحصته من الثمن
Translation: The buyer may take the amount present for its proportionate share of the price.

Bi-hissatihi min al-thaman means allocating the agreed price to the quantity actually available. If 100 qafiz were promised for 100 dirhams and only 80 exist, the buyer may take the 80 for 80 dirhams.

The price can be apportioned because units of this measured grain function as quantities that correspond to parts of the consideration.

4. Shortage: rescinding the entire sale

وإن شاء فسخ البيع
Translation: Or the buyer may rescind the sale.

The buyer bargained for 100 qafiz. The remaining 80 may not serve the intended purpose, even at a reduced price: the buyer may need one complete supply from the same lot.

The option of rescission protects assent to the bargain as a whole. Accepting the reduced price is a choice, not an obligation.

5. Calculating an apportioned price

For an apportionable measured commodity, use:
Actual quantity ÷ Agreed quantity × Total price

Case 1: 75 of 100 qafiz, originally 100 dirhams → 75 dirhams.
Case 2: 30 of 40 measures, originally 2,000 rupees → 1,500 rupees.
Case 3: 45 of 50 measures, originally 5,000 rupees → 4,500 rupees.

These calculations are illustrations of divisible, measured goods. Do not apply the formula automatically to every item described by size.

6. Why division of the bargain matters

The full price originally corresponded to the full specified quantity. A portion is now missing, so the price of the available measures can be determined proportionately.

The juristic idea of division of a single bargain (tafarroqu al-safqah) explains why the buyer may reject a partial fulfilment. The original consent was to one complete bargain.

The doctrine therefore combines a proportional consideration with an option not to accept the divided transaction.

7. Surplus in a measured heap

وإن وجدها أكثر فالزيادة للبائع
Translation: If the heap is found to contain more, the surplus belongs to the seller.

The sale covered 100 qafiz, but the heap measures 115. Only 100 were contracted for; the additional 15 were not sold.

An observable physical surplus is not automatically a free bonus. Where the commodity is sold in divisible, measured units, the excess units remain with the seller.

8. Why deficiency and surplus are different

A deficiency leaves the buyer without a part of the promised goods, giving an option to accept proportionally or rescind. A surplus, by contrast, consists of quantities that were never sold.

90 found instead of 100 → 90 at proportional price, or rescission.
110 found instead of 100 → 100 bought; 10 remain the seller’s.

A buyer’s option and ownership of surplus are distinct legal questions.

9. Measured portions versus attributes

The next cases involve one identified cloth or plot of land. A measurement may function as a description or attribute of that one thing rather than independent units sold separately.

“Take this whole cloth for 10 dirhams; it is 10 cubits long” differs from “this cloth, each cubit for 1 dirham.”

The legal treatment of excess and deficiency changes depending on which contractual structure was chosen.

10. Short cloth or land: the stated rule

ومن اشترى ثوبا على أنه عشرة أذرع بعشرة دراهم أو أرضا على أنها مائة ذراع بمائة درهم فوجدها أقل فالمشتري بالخيار
Translation: Whoever buys a cloth described as 10 cubits for 10 dirhams, or land described as 100 cubits for 100 dirhams, and finds it shorter or smaller has an option.

Here a single identified cloth or piece of land is sold for an aggregate price. The cited dimension describes the desired quality or extent of that object.

A shortfall gives the buyer an option because the represented attribute is missing; it does not automatically establish a separately priced cubit in this formulation.

11. Lump-sum shortage: full price or cancellation

إن شاء أخذها بجملة الثمن وإن شاء تركها
Translation: If the buyer wishes, the buyer takes it for the entire stated price; otherwise the buyer may leave the sale.

Suppose an identified cloth is sold for a lump sum of 10 dirhams, represented to be 10 cubits, but is found to be 8 cubits. The buyer may:
1. Accept the same cloth for the entire 10-dirham price.
2. Reject the transaction.

The buyer is not automatically entitled to pay 8 dirhams in this particular contract structure. That is the key difference from the measured-grain case.

12. Why an attribute gets no separate price

Length affects the usefulness and value of cloth, but in this precise sale it is an attribute of one identified article, not a separately priced portion of it.

The classical legal analysis says that the attribute is not independently assigned a share of the aggregate consideration. Failure of the represented attribute triggers the buyer’s option, not an automatic reduction of the full price.

Contemporary property agreements may contain additional terms and law; this classical example should not be applied to them without analysing the contract.

13. Land example: described area at a lump sum

An identified plot is described as 100 cubits and sold as a single property for 100 dirhams. If measurement yields 90, the buyer may either keep that identified plot for 100 or reject it.

A 90-cubit finding does not automatically reduce the price to 90 in this formulation. The dimension was specified as a description, not a separately valued unit.

14. Lump-sum cloth or land: surplus

وإن وجدها أكثر من الذراع الذي سماه فهو للمشتري ولا خيار للبائع
Translation: If it is found larger than the specified cubit-measure, the extra belongs to the buyer and the seller has no option.

An identified cloth is described as 10 cubits but proves to be 12. In this lump-sum sale, the entire identified cloth belongs to the buyer; additional length improves the described attribute of that same item.

The seller does not acquire an option to demand a new price for the two extra cubits or cancel on that account.

15. Comparing surplus grain and longer cloth

Compare the two surplus cases:
Grain: 100 measured units contracted, 110 available → 10 additional units remain the seller’s.
Cloth: a whole identified cloth bought for 10 dirhams, described as 10 cubits but found to be 12 → the entire cloth belongs to the buyer.

These rulings are not contradictory. What exactly was sold differs: separate measurable units in one case, an identified article with a described attribute in the other.

16. A third form: explicitly priced cubits

A third structure expressly says “one dirham for every cubit.” This goes beyond describing length; the contract attaches a monetary amount to each cubit.

The dimension is now independently relevant to the consideration. If a stated 100-cubit item measures 90, the calculation differs from the pure lump-sum cloth or land sale.

The added pricing phrase changes the rule; these cases must not be collapsed.

17. Shortage under per-cubit pricing

وإن قال بعتكها على أنها مائة ذراع بمائة درهم كل ذراع بدرهم فوجدها ناقصة فهو بالخيار
Translation: If the seller says, “I sell it as 100 cubits for 100 dirhams, each cubit for one dirham,” and it is found deficient, the buyer has an option.

Both the aggregate price and the explicit per-cubit price are named. If the item proves to have 90 cubits instead of 100, the stated unit rate makes proportional pricing meaningful.

The phrase “he has an option” refers to the buyer. The altered extent cannot simply be imposed as the same bargain.

18. Per-cubit shortage: two possible choices

إن شاء أخذها بحصتها من الثمن وإن شاء تركها
Translation: The buyer may take it for its proportional share of the price, or leave the sale.

If 100 cubits cost 100 dirhams at an explicit one dirham each, and only 90 are found, the buyer may:
1. Take the 90 cubits for 90 dirhams, or
2. Decline the sale.

If the same identified land had merely been sold as “100 cubits for a lump sum of 100,” proportionate price would not automatically follow. The explicit unit-price clause changes the analysis.

19. How an attribute becomes separately priced

Length ordinarily describes a particular cloth. But the contract that expressly fixes one dirham per cubit gives each unit a separate role in pricing.

Hanafi commentary explains that an attribute becomes analogous to an independently priced component once consideration is explicitly assigned to it. Requiring the whole price for fewer cubits would then contradict the stated unit rate.

These are terms used to explain price allocation, not a claim that the cloth physically becomes separate garments.

20. Surplus under per-cubit pricing

وإن وجدها زائدة فالمشتري بالخيار
Translation: If it is found to exceed the stated quantity, the buyer has an option.

This is unlike the surplus in a lump-sum cloth sale. Once each cubit has a separate price, an additional cubit can entail additional consideration.

The buyer is neither automatically entitled to every extra unit at the old aggregate price nor forced to pay more without a choice. The following words state the available alternatives.

21. Per-cubit surplus: pay the larger total or cancel

إن شاء أخذ الجميع كل ذراع بدرهم وإن شاء فسخ البيع
Translation: The buyer may take all of it at one dirham for every cubit, or rescind the sale.

The contract stated 100 cubits at one dirham each; 110 are found. The buyer may:
1. Take the entire 110 cubits for 110 dirhams, or
2. Rescind the sale.

Taking all 110 for only 100 is not the option stated for this contract. The extra length brings an added payment obligation, so the buyer retains a choice.

22. Three price structures side by side

Case 1 — measured grain, 100 qafiz for 100:
90 found → take at 90 or rescind.
110 found → extra 10 belong to seller.

Case 2 — identified cloth, said to be 100 cubits for a lump sum of 100:
90 found → accept at 100 or rescind.
110 found → the whole cloth belongs to buyer at 100.

Case 3 — identified cloth, 1 dirham per cubit:
90 found → take at 90 or rescind.
110 found → take all at 110 or rescind.

The object sold and the wording that allocates price explain the three distinct outcomes.

23. Two contracts describing the same plot

Assume the same identified plot actually measures 90 cubits.

First wording: “This whole plot for 100 dirhams; it is 100 cubits.” The buyer may keep it for the full 100 or reject it.

Second wording: “This plot as 100 cubits for 100 dirhams, each cubit for one.” The buyer may take it for 90 or reject it.

One numerical discrepancy can have different consequences because the agreed allocation of consideration is different.

24. When the buyer’s agreement must be reconsidered

A discrepancy can change what the buyer originally consented to.

Less measured grain means part of the purchased quantity is missing.
A shorter cloth sold as an entire item lacks a represented attribute.
Under per-cubit pricing, a shortfall reduces delivered units while a surplus increases the total payment.

Each issue can trigger a buyer’s option for a different reason. The price consequence is not uniform.

25. Common mistakes in applying these rules

Mistake 1: Automatically reducing the price for every shortage. A lump-sum cloth case differs.
Mistake 2: Treating surplus measured grain as a free benefit for the buyer; the surplus remains the seller’s.
Mistake 3: Assuming the original total is unchanged despite an explicit per-cubit price and extra cubits.
Mistake 4: Ignoring the buyer’s stated option and compelling acceptance of a changed bargain.

Always read the exact contractual wording before assigning a result.

26. Applied case: 32 instead of 40 measures

Forty measures of grain cost 2,400 rupees, but only thirty-two exist.

Price per measure: 2,400 ÷ 40 = 60.
Price for 32: 32 × 60 = 1,920 rupees.

The buyer may accept the 32 at 1,920 or rescind. A calculable refund does not eliminate the option to reject incomplete performance.

27. Applied case: 225 instead of 200 cubits

An identified cloth is sold as “200 cubits, total 200 dirhams.” If this is a lump-sum sale of the whole cloth and it is 225 cubits, the entire cloth goes to the buyer at the agreed total.

If the sale instead expressly says one dirham per cubit, the buyer can take all 225 for 225 or rescind.

The same extra 25 cubits are treated differently because the contractual pricing was different.

28. Key Arabic expressions and their function

Ibta‘a: bought.
Sabrah: a defined heap, here of grain.
Qafiz: a historical grain-capacity measure.
Bi-hissatihi min al-thaman: at its proportionate share of the price.
Bi-jumlat al-thaman: for the entire aggregate price.
Dhira‘: a cubit or length measure.
Kullu dhira‘ bi-dirham: one dirham assigned to each cubit.
Fasakh al-bay‘: rescind the sale.

The contrast between “proportionate share” and “full price” helps distinguish the cases.

29. Final doctrinal synthesis

Ask three questions:
1. Is it a divisible, measured commodity? A shortage permits proportionate acceptance or rescission; surplus measures remain the seller’s.
2. Is one identified cloth or plot sold for a lump sum, with a described size? A shortage permits acceptance at full price or rescission; extra size belongs to the buyer.
3. Does every cubit have its own expressly fixed price? Both shortage and surplus change the price at that rate, while the buyer retains the stated option.

The next consecutive Quduri passage begins with “wa-man ba‘a daran dakhala bina’uha fi-l-bay‘”, concerning what is included in the sale of houses, land, trees and crops.