Al-Shafii attacked istihsan, juristic preference, directly and by name, arguing in his own foundational work that a jurist who sets aside the result an established method would reach in favour of what merely seems more fitting has legislated rather than derived a ruling from revelation. The Canonization of Islamic Law: A Social and Intellectual History records the argument as one of al-Shafii's sharpest and most sustained polemics, framed against the jurists of Iraq, chiefly the early Hanafi school, whose use of istihsan he read as reopening to private judgement exactly the space that revelation, properly interpreted through a stated method, had already settled. Al-Risala fi Usul al-Fiqh sets out the positive alternative al-Shafii offers in place of preference exercised at a jurist's discretion, a hierarchy of sources, Quran, Sunna, consensus and analogy, that a jurist is bound to work through in order rather than departing from when the result feels wrong. The rejection is counted among the defining commitments of the Shafii school precisely because it is not one ruling among many but a claim about method itself, that legal reasoning owes an account of the specific textual warrant behind every conclusion rather than an appeal to what a jurist judges preferable.