I was inspired to start this forum after reading Ibn Hazm Al-Andalusi's book
إبطال القياس والرأي والاستحسان والتقليد والتعليل (Invalidation of analogy, opinion, preference, imitation, and justification).
He makes this succinct conclusion on the last page of the book,
قول جامع
من المحال الباطل أن يكون الله يأمرنا بالقياس، أو التعليل، أو الرأي، أو التقليد، ثم لا يبين لنا: ما القياس؟ وما التعليل؟ وما الرأي؟ وكيف يكون كل ذلك؟ وعلى أي شيء نقيس؟ و بأي شيء نعلل؟ وبرأي من نقبل؟ ومن نقلد؟ لأن هذا تكليف ما ليس في الوسع، وبالله التوفيق.ـ
Translation:
It is impossible that God would charge us with analogy, opinion, or following before He would explain to us what they are, how they are done, whose opinion we are to accept and whom to follow, because that would be a charge beyond capacity.
That may very well be the end of discussion about the subject!
But we want to go through the arguments of the scholars analyzing them and determining what they actually said and how we can determine its validity.