Is it permissible to sell walnuts by counting a sample measure, and then taking the entire lot based on that sample count?

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It is not permissible for a man to count a measure as one thousand walnuts, and then take the entire lot based on that standard measure, according to Imam Ahmad. Similarly, if a man purchases bales (*a'kam*) of measured goods and tells the seller to measure one bale individually and base the rest of the quantity on that measure, Imam Ahmad dislikes this until all bales are measured. Al-Thawri stated that their companions disliked this because the contents of the bales differ, meaning measuring some does not reveal the quantity of the rest. Since walnuts vary in count, one container may hold more than another, making estimation by measuring only a part invalid, analogous to estimating measured goods by weight or weighed goods by measure.