A defense to a copyright infringement claim. The statutory factors in such a defense are (1) the purpose and character of the use, (2) the nature of the copyrighted work, (3) the amount of the work used, and (4) the economic impact of the use. 17 USCA § 107. Anyone is entitled to use copyrighted material in a reasonable manner without the consent of the owner. Quoting from a book is a fair use.
The ultimate goal of copyright is to expand public knowledge and understanding, which copyright seeks to achieve by giving potential creators exclusive control over copying of their works, thus giving them a financial incentive to create informative, intellectually enriching works for public consumption. This objective is clearly reflected in the Constitution's empowerment of Congress 'To promote the Progress of Science . . . by securing for limited Times to Authors . . . the exclusive Right to their respective Writings.' U.S. Const., Art. I, § 8, cl. 8) (emphasis added). A similar message is reflected in England's original copyright enactment, 'An Act for the Encouragement of Learning, by Vesting the Copies of Printed Books in the Authors,' which explains as its purpose 'the Encouragement ...