Reasonable on 23 January 2010
Whoever discovered you could make tools
Whoever discovered you could make fire
Whoever discovered written word
A whole heap of ancient mathematician / philosophers
Galileo and other often persecuted soles who looked to the skies and reported the truth
Ts’ai Lun and Johan Gutenbery
Einstein
Newton
Darwin
No-one religious for me, in the long run I expect all of them to become irrelevant. Same for famous conquerors, etc. Transient events of little real note.
Major advancements only IMHO.
Try to be reasonable... its easier than you think...