فصل في القياس الشرعي
Legal analogy.
هو ترتيب الحكم في غير المنصوص عليه على معنى هو علة لذلك الحكم في المنصوص عليه
It establishes a ruling in an unaddressed case through the meaning that is the effective cause of the ruling in the textually addressed case.
Qiyas does not rest on outward resemblance. A ruling is first established in the original case, its legally effective cause is identified, and the jurist then determines whether that cause exists in the new case. Extension remains subject to superior evidence.