[extropy-chat] Maths ability (was: Fight for Evolution?)

[scerir]

ben:
[...] i still don't know 
the answer to (-1) - (-1). 

That seems to be easy. But there
are several mysteries ....  
[1]
http://photos1.blogger.com/blogger/4139/2366/1600/bild1.jpg
[2]
http://photos1.blogger.com/blogger/4139/2366/1600/bild2.jpg
[3] 
http://photos1.blogger.com/blogger/4139/2366/1600/bild3.jpg

Grothendieck invented his 'universes' to provide sets 
in which mathematics can be performed easily and 
consistently but, as you can see, .... :-)
http://en.wikipedia.org/wiki/Grothendieck_universe