Re: Using non-GPL libraries in a GPL program

[Alexander Terekhov]

Dave Crossland wrote:
[...]
> The works that are subject to copyright must be licensed "as a whole"
> under the GPL. The works that are public domain are not subject to
> copyright. Hence it is absolutely trivial to have a derivative work
> based on preexisting public domain material copyright licensed under
> the GPL.

Given: D is a derivative work "as a whole" employing public domain
expression P. 

The copyright on D (i.e. stuff that you can copyright license) covers
only D - P = C expression. "As a whole" expression is C + P = D. To
repeat: stuff that can be copyright licensed is only C and not P. Hence
(now try concentrate your brain power)

                                C < D

which means that D can not be licensed "as a whole" under the GPL.

That's impossible because C < D. 

Grok it now?

regards,
alexander.

--
http://gng.z505.com/index.htm
(GNG is a derecursive recursive derecursion which pwns GNU since it can
be infinitely looped as GNGNGNGNG...NGNGNG... and can be said backwards
too, whereas GNU cannot.)