Quotation:

 B. F. Skinner quotes

 Paul Sweeney quotes

 Thomas Babington Macaulay quotes (English Historian, 1800-1859)

 William Styron quotes (American Writer and Novelist, He is noted for his treatment of tragic themes and his use of a rich, classical prose style (Confessions of Nat Turner.). b.1925)

 Oscar Wilde quotes (Irish Poet, Novelist, Dramatist and Critic, 1854-1900)

 William Glasser quotes ( , b.1925)

 Maya Angelou quotes (American Poet, b.1928)

 Groucho Marx quotes (American Comedian, Actor and Singer, 1890-1977)

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 Robert M. Hutchins quotes (American Educator and Writer, active in forming the Committee to Frame a World Constitution (1945), led the Commission on Freedom of the Press (1946), and vigorously defended academic freedom, opposing faculty loyalty oaths in the 1950s. 1899-1977)

 F. Sagan quotes