On Tue, May 5, 2009 at 10:41 PM, Robert Bradshaw <rober...@math.washington.edu> wrote: > > On May 5, 2009, at 9:23 PM, Brian Granger wrote: > >> Michael, >> >> Thank you for bringing up this issue as it does clarify some aspect of >> Sage derived code and licensing. But, in my mind, the "sage as >> interpreter" aspect is a small perturbation on top of the zero-order: >> >> Sage = Python + GPL libraries >> >> That is, for the most part, I view the interpreter as Python itself. >> But still the FAQ section is very clear that the presence of all the >> GPL libraries loaded into an interpreter is sufficient to make sage >> using scripts like Ondrej's GPL bound. I also understand that not >> everyone agrees on this interpretation. > > The concept of "derivative work" transcends the GPL, what was quoted > was the FSF's interpretation of copyright law, which is obviously > going to be bias towards maximal viral impact. Personally, I think > qualitative aspects are more important than technical aspects (static > vs. dynamic linking) in asking whether or not something is morally or > legally a derivative work. > > One could argue with exactly the same logic that a Mathematica > worksheet is a derivative work of Mathematica, and a Matlab script is > a derivative work of Matlab. (Both are interpreters + large > libraries, with much of the underlying core written in the exact same > language that the end user uses). The copyrights of these two > programs (all rights reserved) don't allow redistribution at all, > does that mean every shared Mathematica/Matlab script (without the > express permission of the respective coorperations) is a violation of > copyright? I think not, and the same applies to Sage worksheets and > scripts.
I think this very much depends on what's written in the license of Mathematica and Maple. I didn't read their license, but I would not be surprised if they do *not* restrict licenses of your own scripts. GPL, on the other hand, speaks about derivative works and licensing your own stuff, that uses a GPLed library/code. So I think that from the fact, that you can license your own Mathematica code using any license you want, doesn't follow that you can license a Sage script using any license you want --- in fact, as William just clarified, if the script uses a Sage code, and you redistribute it publicly, it has to be GPL. William, so do you think that my script A above has to be GPL? I already distributed it publicly on this list. > > The repercussions of this could mean that papers and books couldn't > be published with code snippets in them, one would require copyright > notices for anyone using Sage in their homework (and showing their > work), and we've all been violating the GPL by claiming the wiki is > licensed under Creative Commons. (OK, maybe small snippets could be > justified under fair use, but still...) > >> But in my mind, that was the TRIVIAL part of the original question I >> asked. The more subtle aspect is centered around this issue: >> >> * Does "Sharing" a notebook (with other users of the notebook web app) >> constitute distribution and is that sufficient to trigger the >> application of the GPL? >> >> In other words, do I need to tell my students... >> >> "When you share your Sage notebooks with me and other's in the class, >> you must agree to license them under the GPL" > > I think sharing a worksheet, whether it be clicking on the "publish" > button or emailing/posting a .sws file all have the same > repercussions. In fact, flipping the permissions bit and pointing you > to the file under a shared filesystem with the intent that you read > it would probably classify as "distribution." Ultimately, in the US > system at least, it is the courts that will decide this, but as long > as one is clearly respecting the intent of the GPL (which I don't > think forces Sage scripts to be GPL'd, though of course that's up to > interpretation as well) one retains the respect of the community, and > if one is worried about the nitpicky legal aspects, I doubt any Sage > developer is going to be suing any of your students for copyright > violation for publishing an original notebook :-). But what about FSF suing Brian? > >> Cheers, >> >> Brian >> >> PS[0] = even though I choose to use the GPL myself sometimes, this is >> what I hate about it. It is too damn complicated. Even on a strongly >> pro-GPL project like Sage, it doesn't seem like most people have any >> idea what it says and means. I don't mean to pick on anyone >> individually, but on this thread, I have heard _multiple_ different >> and incompatible interpretations of the GPL. > > I wholeheartedly agree. Sometimes I think it's unfortunate that the > de-facto standard for copyleft licenses ended up being such a lengthy > and messy one. This is one of the beauties of the BSD--it's so clean. > Even the CC got this mostly right (it's two pages of legalize, but > much better than most). However, if one wants to release code in a > copyleft manner, going with the GPL is often a better path than > choosing an obscure/incompatible one. > >> PS[1] = It is even more ironic to me that Ondrej and I are the ones >> arguing for the FSF interpretation of the GPL as we are typically >> found in the pro-BSD camp. From my perspective, many Sage devs and >> users are doing things with Sage derived code that violates the >> canonical interpretation of the GPL. If that is just fine, then does >> the GPL actually mean anything? (I think it does even though there is >> some ambiguity!) > > I don't think it's odd at all--the more draconian interpretation you > have of the GPL the more likely you're to be found in the pro-BSD camp. Exactly, I wanted to point this out too. Ondrej --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to sage-devel-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
