> might use lowercase-f "free" to refer to open source licenses in general That's because "free" and "open source" are exactly the same thing. They refer to th

> might use lowercase-f "free" to refer to open source licenses in general That's because "free" and "open source" are exactly the same thing. They refer to the exact same set of licenses and software (within epsilon of each other). "Open source" is a term coined in 1998 as a synonym for "free software": http://jordi.inversethought.com/blog/5-things-we-have-forgotten-about-open-source/ http://jordi.inversethought.com/blog/5-things-we-have-forgot... When rms is talking about copyleft, he's not saying it's identical to free software. Copyleft is just a tool he advocates in order to promote free software, but it's not a goal in itself, nor a requirement for software to be free.