I would consider those very different, actually. When you only allow copyleft licenses you become a social movement, whereas open source is a software developme

I would consider those very different, actually. When you only allow copyleft licenses you become a social movement, whereas open source is a software development methodology. Edit: I must be way out of date, or something. I was under the impression that all Free Software had to have a requirement that derivative works also be published under a Free Software license. This doesn't seem to be true. I would agree, then, that they are basically the same.