Perhaps the choice of license is orthogonal to the success and openness of the scipy community — the big competitors are closed source and anything open is incredibly attractive to many, and there aren’t that many viable open source alternatives out there. The early developers chose the BSD license and the rest was history. Or, alternatively, perhaps the BSD license is causal to the success the community now enjoys. Big and small companies and organizations do pay people to work on this software, and the BSD license encourages them to do so without fear of being unable to release closed source apps.

It’s difficult to distinguish between these alternatives conclusively, but my belief is that the BSD license is causal to the success of the scipy community. In particular, the company Enthought, which employs many key developers, needs a solid infrastructure for higher-level, closed-source apps they write and sell. I think their support has been quite significant, and even if the community has now reached a critical mass that could sustain continued growth, I think much of the early efforts benefitted directly from the choice of BSD license. (By the way, a founder of Enthought wrote an interesting post related to these issues.)

And frankly the BSD-is-more-free argument is so obviously a logical trick that I find the argument intellectually dishonest.

(I wasn’t sure if it was necessary to be tell people not to rant about the GPL in my last post, but that this post so quickly degenerated into this oft-repeated discussion of freedom makes it apparent that I was right to do so)

It is however less freedom than one gets with the BSD license, because you can opt to use under closed source, and BSD has less restrictions.

There are various shades of “freedom”. The GPL is a very strict one. It does not necessarily have to be good or bad, but we all must acknowledge that it is stricter than the BSD.

Copyright law reserves the right of redistribution of a work to the copyright holder. The GPL is allowing other parties this right, so long as they follow the conditions the copyright holder has chosen (through applying the GPL to the work).

If they don’t like those conditions, nothing about the GPL is “forcing” them to release their modified work at all. That’s a freedom they can always exercise if they choose, but only under the conditions of the license under which they received the work. This is much more freedom than the offers they’ll get for most other copyrighted works.

We don’t live in that world, fortunately: we as a society restrict behaviour because we judge that behaviour more harmful than the corresponding reduction in freedom. One way I’ve heard this expressed is the phrase “Your freedom to swing your fist ends at the tip of my nose”.

We are then faced with the choice of which freedoms are important for people to have in our society, and which are not desirable to preserve.

The GPL makes clear that “can impose restrictions on other people that were not imposed upon me” is not a freedom desirable to preserve. It does this through the condition that I may only redistribute the software under the same license terms as I received them.

IanB: thanks for a nice summary. I’m glad to see you expressing changed opinions as they come, whether from new information or further reflection.