Reference for Bava Kamma 129:6

אמרי משום דא"ל אנא פטימנא ואת שקלת

Come and hear: [If a thief misappropriated] a fat animal and caused it to become lean, he has to pay double payment or fourfold and five-fold payments according to the value at the time of theft. [Does this not contradict the ruling enunciated by Rab?]<span class="x" onmousemove="('comment',' V. p. 376, n. 11. ');">¹¹</span> — There also [the thief has to pay thus] because we argue against him 'What is the difference whether you killed it altogether or only half-killed it.'<span class="x" onmousemove="('comment',' The liability thus began at the time when the thief caused the animal to become lean. ');">¹²</span>

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