Richard Stallman (1953 - now) is an American programmer best known for his contributions to the free software movement and starting the GNU Project in 1983. The rest of this post is some quotes from Stallman.
1. "I consider that the Golden Rule requires that if I like a program, I must share it with other people who like it. Software sellers want to divide the users and conquer them, making each user agree not to share with others. I refuse to break solidarity with other users in this way." (GNU Manifesto, 1985)
2. "GNU is not in the public domain. Everyone will be permitted to modify and redistribute GNU, but no distributor will be allowed to restrict its further distribution. That is to say, proprietary modifications will not be allowed. I want to make sure that all versions of GNU remain free." (GNU Manifesto, 1985)
3. "The term 'free software' has an ambiguity problem: an unintended meaning, 'software you can get for zero price' fits the term just as the intended meaning, 'software which gives the user certain freedoms'." (Why 'Free Software' is Better than 'Open Source', 1998)
4. "The official definition of 'open source software' as published by the Open Source Initiative, is very close to our definition of free software; however it is a little looser in some respects, and they have accepted a few licenses that we consider unacceptably restrictive of users. However, the obvious meaning for the expression 'open source software' is, 'you can look at the source code'. This is a much weaker criterion than free software; it includes free software, but also some proprietary programs... That obvious meaning for 'open source' is not the meaning that its advocates intend. The result is that most people misunderstand what those advocates are advocating." (Why 'Free Software' is Better than 'Open Source', 1998)
5. "To be able to choose between proprietary software packages is to be able to choose your master. Freedom means not having a master." (The Free Software Movement and the Future of Freedom, 2006)
