In his book التبيان في الناسخ والمنسوخ في القرآن المجيد, Aş-Şa`di Al-Yamaani points out on page 71 that the Arabs often use the negative article لا, not for negation but for negativity.
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He mentions this to explain the opinion of As-Suddi and Yahya ibn Al-Husayn aka Al-Haadi who said the meaning of يطيقونه (can barely do it) is لا يطيقونه (cannot do it).
I am sorry, but the logic doesn't go through. He established that the use of
لا may not mean negation. He did not establish that the
lack of use of
لا may mean negation.
Dr. M. Ibrahim Faaris, in his presentation of Shu`la's book صفوة الراسخ في علم المنسوخ والناسخ, page 72, mentions two interesting pieces of evidence that the lack of mentioning the negative article has been used in Arabic to mean negation!
His first evidence is compelling! (12:85),
The literal translation would be: They (Jacob's sons) said [to him], "By God, you
cease to mention Joseph until you become prey or become one of the perished." Jacob's sons (PBUH) meant "By God you are
never going to stop mentioning Joseph..."
The other evidence is a line of poetry, which Dr. Faaris tried all he could to find anywhere else and failed:
أوصيك أن يحمدك الأقارب...ويرجع المسكين وهو خائب
Literal translation would be: I bequeath you that kin praise you and that
the poor return disappointed! But the meaning, as the Arabs would get it, is that the poor
do not return disappointed.