- Christopher Hitchens
- Steven Pinker
- Stephen Jay Gould
- Charles Darwin
- Ann Druyan
- Sam Harris
- Bertrand Russell
- Matt Ridley
- Michael Shermer
- Lawrence M. Krauss
- Roger Penrose
- Robert Wright
- Ralph Leighton
- Neil deGrasse Tyson
- Carl Zimmer
- Freeman Dyson
- Russ Kick
- Martin J. Rees
- Susan Blackmore
- Victor J. Stenger