Bidayat al-Mujtahid (The Distinguished Jurist's Primer) – Ibn Rushd

It is considered one of the most important books dealing with the science of jurisprudential disagreement. Despite its small size, it contains the most important issues of jurisprudence, clarifying points of agreement and disagreement, explaining the different schools of thought, mentioning the sayings of scholars for each jurisprudential issue, drawing attention to the nuances of disagreement therein with a discussion of opinions and evidence without fanaticism, and the book is considered one of the most important books of comparative jurisprudence.