Why is opening an archway (taq) or a door in a wall not permitted by analogy with placing wood?

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The opening of an archway or a door in a wall is not permitted by analogy with placing wood because the wood supports and benefits the wall. In contrast, an archway or a door weakens the wall as it remains open within it, whereas the opening made for the wood is closed by the wood itself. Moreover, placing wood is necessitated by need, unlike opening an archway or door.