ولو سقط من يد الصبي فجرحه يضمن.
If the knife instead falls from the child's hand and injures him, the original example assigns liability to the giver.
The contrasting outcomes depend on the intermediary's nature. In the first situation a later voluntary act is attributed to the child. In the second, the fall is not an equivalent independent voluntary action.
Where the consequence cannot be attributed to an independent intervening act, attribution may revert to the earlier facilitating cause. The same object is involved in both cases; the legal difference lies in the intervening conduct.