Ibn Khaldun on Science: The Prophet was sent to teach Religious Law, not ordinary technical matters

Ibn Khaldun wrote in his Al-Muqadimah, the Introduction:

والطب المنقول في الشرعيات من هذا القبيل وليس من الوحي في شىءوإنما هوأمر كان عادياً للعرب‏.‏ ووقع في ذكر أحوال النبي صلىالله عليهوسلم من نوع ذكرأحواله التي هي عادة وجبلة لا من جهة أن ذلك مشروع على ذلك النحو من العمل‏.‏ فإنه صلى الله عليه وسلم إنما بعث ليعلمنا الشرائع ولم يبعث لتعريف الطب ولا غيره من العاديات‏.

‏The medicine mentioned in the religious tradition is of the Bedouin type. It is in no way part of the divine
revelation. (Such medical matters) were merely part of the Arab custom and happened to be mentioned in connection with the circumstances of the Prophet, like other things that were customary in his generation. They were not mentioned in order to imply that that particular way of practicing medicine is stipulated by the religious law. Muhammad, peace and blessings be upon him, was sent to teach us the religious law (sharia). He was not sent to teach us medicine or any other ordinary matter.

 وقد وقع له في شأن تلقيح النخل ما وقع فقال‏:‏‏ أنتم أعلم بأموردنياكم‏.‏

 فلا ينبغي أن يحمل شيء من الذي وقع من الطب الذي وقع في الأحاديث الصحيحة المنقولة على أنه مشروع فليس هناك ما يدل عليه اللهم إلا إن استعمل على جهة التبرك وصدق العقد الإيماني فيكون له اثر عظيم في النفع‏.‏ وليس ذلك من الطب المزاجي وإنما هو من آثار الكلمة الإيمانية كما وقع في مداواة المبطون بالعسل ونحوه‏.‏

In fact, there occurred concerning the matter of grafting date-palms and the Prophet said, “You are most knowing of your worldly affairs.” So, none of the statements concerning medicine that occur in sound traditions should be considered as (having the force of) law. The only thing is that if that type of medicine is used for the sake of a divine blessing and in true religious faith, it may be very useful. However, that would have nothing to do with humoral medicine but be the result of true faith. This happened in the case of the person who had a stomach-ache and it was treated with honey, and similar stories.

[Ibn, K., In Rosenthal, F., & Thomas Leiper Kane Collection (Library of Congress. Hebraic Section). (1958). The Muqaddimah: An introduction to history. New York: Pantheon Books. p. 387-388]