The man who helped Jewish academics escape Nazi persecution
Mathematician Richard Courant tirelessly used his social networks to help academics to safety.
Birds of a feather: how friends shape our political opinions
How much influence do your friends' opinions have on your own political views? Quite a bit according to research.
This social network changed the world as we know it
Martin Luther's Protestant Reformation brought enormous change, but it couldn't have happened without networks to spread information. Fragments reveal fascinating insights into modern habits.