Jurisprudence is the theory and philosophy of law. Scholars of jurisprudence, or legal philosophers, hope to obtain a deeper understanding of the nature of law, of legal reasoning, legal systems and of legal institutions. The different roles of case law in civil and common law traditions create differences in the way that courts render their decisions. Common law courts generally explain in detail the rationale behind their decisions with numerous citations to previous decisions and other authority (called ratio decidendi). By contrast, decisions in the courts of most civil law jurisdictions are generally very short, referring only to the statutes used. The reason for this difference is that in these civil law jurisdictions the tradition is that the reader should be able to deduce the logic from the decision. Courts in civil law jurisdictions also render their decisions so that in some cases it is somewhat difficult to apply previous decisions to the facts presented in future cases.
Another difference is that law professors in common law traditions play a much smaller role in developing case law than professors in civil law traditions. Because court decisions in civil law traditions are brief and not amenable to establishing precedent, much of the exposition of the law in civil law traditions is done by academics rather than by judges, this is called doctrine and may be published in treatises or in journals such as Recueil Dalloz in France. In the common law the practice has evolved in the other direction, thus at the turn of the twentieth century it was very rare to see an academic writer quoted in a legal decision (except perhaps for Blackstone). Today academic writers can be cited in legal decisions as authority, often they are cited when judges are attempting to find reasoning that has yet to be adopted by any other court or because their restatement of the law is more compelling than the ratio of precedent. Thus common law systems are adopting one of the approaches long established in civil law jurisdictions.