A theory of law and legal reasoning that arose in the early decades of the twentieth century broadly characterized by the claim that law can be best understood by focusing on what judges actually "do" in deciding cases, rather than on what they say they are doing. The central target of legal realism was legal formalism: the classical view that judges don't make law, but mechanically apply it by logically deducing uniquely correct legal conclusions from a set of clear, consistent, and comprehensive legal rules. American legal realism has aptly been described as "the most important indigenous jurisprudential movement in the United States during the twentieth century".