Since the earliest days, philosophers have dreamed of a country where the mind and spirit of man would be free; where there would be no limits to inquiry; where men would be free to explore the unknown and to challenge the most deeply rooted beliefs and principles. Our First Amendment was a bold effort to adopt this principle — to establish a country with no legal restrictions of any kind upon the subjects people could investigate, discuss, and deny.

Hugo Black (1886-1971) American politician and jurist, US Supreme Court Justice (1937-71)

James Madison Lecture, NYU School of Law (1960-02-17)
    (Source)

The inaugural Madison lecture. Reprinted as "The Bill of Rights," NYU Law Review, Vol. 35 (Apr 1960)