[extropy-chat] Tyranny in place

[spike]

> bounces at lists.extropy.org] On Behalf Of Eliezer S. Yudkowsky
...
> 
> Heinlein had a sympathetic character say, in one of his stories:  "Logic
> is a fine thing, but I have seen a perfectly logical proof that 2 = 1."
> (If anyone remembers which story this is from, please let me know.)
> 
> Heinlein was probably thinking of this:
> 
> x = y = 1
> x = y
> x^2 = xy
> x^2 - y^2 = xy - y^2
> (x+y)(x-y) = y(x-y)
> x+y = y
> 2 = 1
> 
> Now you could look at that, shrug, and say, like Heinlein, "See, I told
> you logic doesn't always work."... Eliezer S. Yudkowsky

Thanks Mr. Heinlein, love your stories, and I agree that logic does not
always work.  But logic worked perfectly in the example you provided:
 
 x = y = 1
 x = y
 x^2 = xy
 x^2 - y^2 = xy - y^2
 (x+y)(x-y) = y(x-y)
 (2)*(0)= (1)*(0)
 0=0  QED.

Or if you insist on dividing by zero in step 6, then 

undefined = undefined.  QED

spike