If one writes two letters in one state of unawareness, he is culpable. If one writes with ink, chemicals, Sikra, kumos, kankantum, or with anything that leaves a mark on the angle of two walls or on the two leaves [tables] of a ledger, and they [the two letters] are read together, he is culpable. If one writes on his flesh, he is culpable: He who scratches a mark on his flesh, R. Eliezer [T2 or T5] declares him liable to a sin-offering; but the Sages exempt him.
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