The greatest obstacle to discovery is not ignorance - it is the illusion of knowledge.

Daniel Joseph Boorstin (1914 CE-2004 CE), Daniel Joseph Boorstin was an American historian at the University of Chicago who wrote on many topics in American and world history. He was appointed the twelfth Librarian of the United States Congress in 1975 and served until 1987. He was instrumental in the creation of the Center for the Book at the Library of Congress.