Who are the People of Opinion mentioned in the books of Fiqh?

The term "Ahl al-Ra'y" (people of opinion/reasoned legal thought) was predominantly used in books of Fiqh (Islamic jurisprudence) and Hadith to refer to the Hanafis, such as Abu Yusuf and Muhammad ibn al-Hasan, the students of Abu Hanifa. This term means that they originated "ra'y" and "ra'y" originated them, so it became more associated with them than with others. This includes Qiyas (analogical reasoning), Istihsan (juristic preference), and Dhara'i' (means/expedients).