More from Michael Crichton
- State of Fear (2004)
- Environmentalism as a Religion (2003)
- Testimony before the US Senate Committee on Environment and Public Works (28 September 2005)
People/Michael Crichton/Quote

Professor Johnston often said that if you didn’t know history, you didn’t know anything. You were a leaf that didn’t know it was part of a tree.
Timeline (1999), Chapter 2, “Dordogne” (p. 85)
Quote and source from Wikiquote, CC BY-SA 4.0