Last week, Matthew Wilson shared a very correct take on Twitter:

A few people in the mentions argued that the GPL is doing it wrong by his definition. This is incorrect. Copyleft licenses do not prevent the user from doing things, they ensure that subsequent users can do the same thing.

This may seem like a semantic argument, but there’s substance to it. All licenses (except those that amount to a public domain dedication) contain some conditions, minimal though they may be. It’s important to remember that the default is that you can do nothing with a work. Copyright is by definition a monopoly on a work.The entire point of free and open source software licenses is to tell you what you can do, because the default position is that you can’t.

One of the most annoying things about license wars is the argument that one category of license is somehow more free than another. That’s dumb. Both copyleft and permissive licenses promote freedom, just from different perspectives. Permissive licenses give the next person in line the freedom to do (essentially) whatever they want. Copyleft licenses preserve freedoms for all subsequent users, no matter how many hands the work passes through. There are plenty of philosophical and practical reasons you might choose one class of license over the other (I tend to prefer copyleft licenses, myself), but it’s wrong to paint one or the other as anti-freedom.

Getting back to Matthew’s point, there has been a fair amount of license weaponization in the last few years. By this I mean the use of a license to try to exclude a certain class of user. Some of this I’m sympathetic to (e.g. the “ethical source” movement), some of this I’m not (e.g. the various “you can do what you want, just don’t make a successful software-as-a-service offering” licenses that have popped up). In both cases, I think copyright is the wrong mechanism for achieving the goals.

Excluding classes of users is antithetical to ideals free software and open source. That may be okay. As I’ve written, free software is not the end goal. But if you’re going to claim to be open source, you should act open source.