What happens when you mix George Soros' "The Age of Fallibility", Carl Sagan's "The Demon Haunted World" and Mexican movie "Y tu mamá también"?  You end up realising that in the end they might not be so far away from each other.

Basically, their main tenet is that absolute truth is non-existent and we can only reach approximations.  Furthermore, we have to be aware of this fact whenever we are constructing our visions of reality, as assuming they are "true" will only cause us several problems: with the policies and attitudes followed by society, with our use of science and technology, and with our understanding of ourselves.