More than 150 years into development of the doctrine of "fair use" in American copyright law, there is no end to legislative, judicial, and academic efforts to rationalize the doctrine. Its codification in the 1976 Copyright Act appears to have contributed to its fragmentation, rather than to its coherence. As did much of copyright law, fair use originated as a judicially unacknowledged effort via the law to validate certain favored practices and patterns. In the main, it has continued to be applied as such, though too often courts mask their implicit validation of these patterns in the now-conventional "caseby- case" application of the statutory fair use "factors" to the defendant's use of the copyrighted work in question. A more explicit acknowledgment of the role of these patterns in fair use analysis would be consistent with fair use, copyright policy, and tradition. Importantly, such an acknowledgment would help to bridge the often difficult conceptual gap between fair use claims asserted by individual defendants and the social and cultural implications of accepting or rejecting those claims. In immediate terms, the approach should lead to a more consistent and predictable fair use jurisprudence. When viewed in light of recent research by cognitive psychologists and other social scientists on patterns and creativity, in broader terms, the approach should enhance the ability of copyright law to promote creative expression.