There is no such thing as an achieved liberty; like electricity, there can be no substantial storage and it must be generated as it is enjoyed, or the lights go out.

Robert H. Jackson (1892–1954) US Supreme Court Justice (1941–54), lawyer, jurist, politician

“The Task of Maintaining Our Liberties: The Role of the Judiciary,” speech, Boston (24 Aug 1953)
    (Source)

Dinner address at the American Bar Association Diamond Jubilee dinner. Reprinted in the American Bar Association Journal (Nov 1953) [citation 39 A.B.A. J. 961 (1953)].