thinking is dangerous — it leads to ideas
President of the Board of the Polish Free and Open Source Software Foundation. Human rights in digital era hacktivist, Free Software advocate, privacy and anonimity evangelist; expert volunteer to the Panoptykon Foundation; co-organizer of SocHack social hackathons; charter member of the Warsaw Hackerspace; and Telecomix co-operator; biker, sailor.
'UPDATE: highlighted the harmfulness of incompatibility of "no derivatives" licenses with libre licenses (including other CC-licenses); heartfelt thanks to Carlos Solís for the Spanish translation. ¡Gracias!
I believe both are specious. And I feel "no derivatives" licenses are both ineffective and counter-productive. Here's why.
So you're an author and you do not wish your work to be twisted or modified to say something you didn't want to say. There are two possibilities of such modification:
The first possibility would be illegal regardless of the license! Nobody has the right to claim your authorship over something you did not create; nobody has the right to modify your work and claim it is still your work. -ND licenses are unnecessary for that purpose, it's already in the copyright law.
As far as derivative works that build upon the original but change the meaning are concerned (without misrepresentation of authorship), I do not feel we need licensing restrictions for that. That feels too close to censorship for my liking — "thou shall not use my own words against me"; "I don't like what you're trying to say so I will use copyright law to stiffle your speech".
Besides, creating parodies is fair use and no amount of "no derivatives" licensing clauses willl change that. Same goes for quotes. Your words will be used in works that say something you do not wish to say, whether you like it or not!
In that sense, "no derivatives" licenses are ineffective.
This argument hinges upon an assumption that some works (memoirs, documentation, opinion pieces) are fundamentally different than others and hence should be preserved as they are.
First of all, all of what I wrote above applies here. Such works cannot be "modified" anyway, "modification" is in fact creation of a derivative work, nobody can (legally) misrepresent authorship or the derived work as the original; such works, also, can be quoted and parodied, regardless of the license. "No derivatives" is ineffective.
"No derivatives" licensing stops people from doing things most of us would say are desirable. Like improving upon some work, creating better arguments or updated versions. Like translating into another language to disseminate knowledge and argumentation. These things are genuinely good, but people that would like to do them will look at the license, and will then get the message they cannot proceed...
More importantly, however, this argument assumes that there is only one context in which a given work can be used. E.g. "an essay on free software" as an article to read and get argumentation from. Or a "memoir" as a historical document describing one's views and fortune.
Thing is, any work can be used in any context, and often is.
Think for a moment about a teacher in an IT class using an essay on free software as educational material, modifying it just a bit so that the class can better understand it or relate to it, or using it as a basis for an in-class discussion. "No derivatives" would not allow for that.
Think about how artists used different kinds of "materials" for their works of art — for example Duchamp's "Fountain". A "memoir" or an "opinion piece" could easily be used in an "art" context, for example as a basis of vocabulary for some free-software scripted (as in: done by scripts in interpreted programming languages) poem writing contest. An example of something similar is HaikuLeaks.
I bet we could find similar haikus in GNU documentation, FSF policy papers, Linux documentation. "No derivatives" would not allow anybody to use these in such a context — and I would say that's a genuine loss.
And in that sense "no derivatives" licenses are counter-productive.
"No derivatives" licensing is also truly harmful.
They make it harder to explain what libre licensing is. Many people believe that any CC or GNU license is "free as in freedom", while in fact CC-*-ND and GNU Verbatim licenses cannot be considered as such. This distinction is both crucial and hard to convey.
They also cause segmentation within the CC/GNU-licensed group of works: some such works (often co-existing on a single OS or in a single repository) are licensed in a way that makes them incompatible with others. Some cannot be modified or used (namely, "no derivatives"-licensed) in new works, while others can.
This muddies the waters, makes libre licensing this much harder to explain and this much harder to take advantage of.