Open Source License Question

Andrew Dalke adalke at
Fri Oct 29 10:43:51 CEST 2004

Michael Foord:
>>> library modules to do a particular job. Using the GPL means someone is
>>> unable to use your work in a business setting.

Joachim Bowman wrote:
> So does the GNU GPL.  Freedom/Open Source and commercial use are two 
> orthogonal concepts.  The two don't interfere in any way.

It so nice to organize things.  Each file is in a directory,
each book on a shelf, each concept on its own axis.  The
Aristotelian logic of one or the other.

But life is full of platypuses.  That's what makes things
messy, fun, frustrating, and interesting.

"Freedom/Open Source" isn't a single dimension.  How can it be
when licenses can be both free and mutually exclusionary?  (See )

Odds are good you can find three licenses A, B, and C such that
A is compatible with B is compatible with C, but where A is not
compatible with C.  A messy space indeed!

Let B be a point in business space.  Let L be a point in the
software licensing space.  The statement "don't interfere in any way"
means that for all B and all L there is a point (B, L) which is
in (business space x licensing space).

That's provably false - choose B = "a company making money selling
binaries but not also distributing source".  Those exist.  Let
L = "a library licensed under the GPL."  Those also exist.  Suppose
company B wanted to include that library as part of the software.
Is (B, L) a point in business space x software licensing space?

The answer of course is no, so we're left with one or more of the
   1. B and L are not orthogonal (I'm backing this one ;)
   2. B is not a valid point in business space (the way GNU would
       like it to be)
   3. L is not a valid point in licensing space (some others would
       like this to be true)
   4. there's another definition of "don't interefere in any way"
   5. using a dimensional space metaphor doesn't make sense (but
       you believe otherwise)
   6. I'm missing some other reason

Let's assume #5 and #6.  I can't think of more reasonable way
to handle #4 under the dimensional metaphor.  From observation
I see that #2 and #3 do exist.  So I'm left concluding that
there is at least one business model which conflicts with at
least one license model.

In other words, I disagree.

But as it turns out, you actually used the phrase "commercial
use" and not "business setting" in your reply.  You've reduced
the high-dimensional "business space" down to a single
binary descriptor, "commercial."

You said you think of the high-dimensional "software license
space" as a single dimension, and your example implies
you think of it as also being binary dimension (is/is not free).

In that restricted, projected subspace then your argument works.
You successfully enumerated all four possibilities in that
narrow view of things.  It just not what the original poster

Life is complex.  Organization helps understanding.  Toy
models give clarity.  But take away an essential complexity
and the toy is a curiosity only; the platypus removed.

Though I think echidnas look cuter than platypuses and are
just as interesting.

				dalke at

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