you kinda asked 2 seperate questions in the thread greendob..
big diffence in who the greatest humans are and who has contributed the most to mankind.
the contributions part is easy. just pick the 5 people who invented the things we could not live without. nothing any modern day religious leader or president has ever done or said even comes close to a contribution i couldnt live without.
as for the greatest humans of all time, who knows. different faiths and cultures will bring a billion different answers. i would imagine biblical icons would hold reign as the greatest humans but you probably have to believe in everything the bible and believe in god in order to make those choices. we all know not everyone believes.