The split between "free software" and "open source" is the defining schism of the software freedom movement. In February 1998, eric-raymond, bruce-perens, and others founded the open-source-initiative and coined the term "open source" as a deliberate alternative to "free software." The rebranding was strategic: "free software" was seen as politically loaded and confusing (due to the libre-vs-gratis ambiguity). "Open source" emphasized practical benefits — better software, more reliable code, faster development — rather than ethical imperatives.
stallman's response, most fully developed in why-open-source-misses-the-point (2007), is that this rebranding is not merely cosmetic but represents a fundamental philosophical error. See also the note stallman-vs-open-source-philosophical-core and the analysis of his broader approach to terminological politics in stallmans-rhetorical-method.
Stallman's Diagnosis
stallman argues that the open source movement focuses on the wrong thing. Open source advocates say: "Look at how good the software is. Look at how fast bugs get fixed. Look at how efficiently distributed development works." These are arguments from practical benefit — what Stallman calls "technocratic" or "pragmatic" arguments.
His counterargument: these practical benefits are real, but they are not the point. The point is that users deserve to control the software they use, as a matter of ethical principle. If proprietary software happened to be more reliable, more secure, and faster than free software, that would not make it ethical. Conversely, free software would still be worth creating even if it were somewhat less efficient than proprietary alternatives.
The distinction matters because it changes what you optimize for. Open source advocates are willing to compromise on freedom if it gains adoption — accepting proprietary drivers, endorsing SaaS platforms, recommending non-free tools. stallman is not willing to make these compromises, because for him freedom is the goal, not a means to better software.
The Strategic Argument
Open source proponents have a counter-argument: framing software freedom as a moral imperative alienates potential allies, makes free software advocates seem like zealots, and slows adoption. Pragmatic arguments — "this is better for your business," "this produces better code" — are more persuasive to corporations and governments.
stallman's response is that this pragmatic framing, while effective at driving adoption, fails to build the movement necessary to defend freedom when it is under attack. If users adopt free software only because it is convenient, they will abandon it when proprietary alternatives become more convenient. Only users who understand why freedom matters will resist the erosion of the four-freedoms.
Practical Divergences
The philosophical split has practical consequences:
The Naming Dispute as Symptom
The gnu-linux-naming dispute is partly a symptom of this deeper schism. stallman's insistence that the operating system be called "GNU/Linux" is not merely about credit; it is about maintaining the visibility of the free software project and its values in a context where "Linux" has become associated with a pragmatic, open source culture that does not share his philosophical commitments.
Stallman's Self-Characterization
stallman does not regard himself as opposed to the open source community in practical terms — he acknowledges that free software and open source advocates often work toward the same immediate goals. His objection is to the philosophy, not the people. He uses the phrase "free software and open source" to acknowledge both without endorsing the open source framing, and consistently corrects interviewers who describe him as an "open source" advocate.
The note stallman-vs-open-source-philosophical-core develops this distinction at length.