What determines whether a finger is considered original or supernumerary when assessing Qisas?

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A finger is considered original if it is one of the expected five digits in their designated places. If a finger is deemed 'supernumerary' simply because it is weak or leaning away from the alignment of other fingers, its weakness does not render it supernumerary, similar to the state of the organ of a physically impotent man. If it is crooked but rooted in the correct position for a missing finger, it retains its status as an original digit.