Free software dates to 1983. Dr. Stallman announced GNU that September, the Free Software
Foundation followed in 1985, and the GPL turned the four freedoms into something you could
enforce in court. By the time anyone said “open source,” the movement it renamed had fifteen
years of code behind it: Emacs, GCC, most of a working operating system.
And the talking mattered as much as the code. In 1991 a Finnish student who’d been steeped
in the GNU world wrote a kernel for fun, licensed it under Dr. Stallman’s GPL, and dropped it
into the fifteen years of GNU userland already waiting for it — that’s Linus Torvalds, and
that’s why Linux became an operating system instead of a hobby tarball. In 1997 Werner Koch
heard Dr. Stallman speak in Germany, urging Europeans to build a free replacement for PGP
that US crypto export law couldn’t touch; Koch went home and wrote GPG, the tool journalists
and dissidents still stake their lives on. No inspiring, no Linux, no GPG. The preacher was
load-bearing.
Open source arrived in 1998, and it arrived as a pitch. Part of the community had decided
that the word freedom was scaring the customers, and they were candid about the fix:
Some of the supporters of open source considered the term a “marketing campaign for free
software,” which would appeal to business executives by highlighting the software’s practical
benefits, while not raising issues of right and wrong that they might not like to hear.
Hide the ethics, sell the method. It worked better than anyone expected. Millions of people
now use and write free software under a different name, and most of them have never once
heard the original argument for it. As Dr. Stallman puts it, most discussion of open source
“pays no attention to right and wrong, only to popularity and success.”
Free means freedom, not price. Free speech, not free beer. A program is free
software when its license respects four freedoms, and every one of them belongs to the person
using the program. They read like a bill of rights because that’s what they are — enumerated,
unalienable, and infringed just as often:
freedom 0
Run it, for any purpose
Use it for anything, on anything, forever. No approved-purposes list. Remember this one — it comes up later.
freedom 1
Study it, change it
Read it, learn from it, rewrite it. Source access exists to serve this freedom, not the other way around.
freedom 2
Redistribute copies
Give a copy to whoever needs one. Helping your neighbor is the design goal, not a piracy edge case.
freedom 3
Share your changed versions
Ship your modifications, so your fixes reach everyone the program reaches.
The GPL was written to guarantee these “for all users of a program,” including someone three
distributors downstream from the author. Copyleft is just freedom with an enforcement
mechanism attached. Dr. Stallman calls the freedoms essential “not just for the individual users’
sake, but for society as a whole,” and here’s the thing: the other camp never actually
disagreed with any of that. They just stopped bringing it up.
The FSF and the OSI both spend their days talking about licenses, which makes them easy to
mix up. Follow the money instead. The OSI runs on corporate sponsorship, and its sponsors are
some of the largest companies on earth. The FSF runs on membership dues from individuals.
FSF est. 1983
Campaigns for the freedom of computer users. That’s the whole mission statement.
Wrote the GPL — “designed specifically to protect freedom for all users of a program” — and defends it.
No corporate members. Funded by individual dues and limited donations that buy no vote and no seat.
Says “freedom” in meetings, unprompted, since 1983.
OSI est. 1998
Approves licenses. (§05 covers the quality control.)
Maintains a definition that never grants you the right to run the program. (§04.)
Founded to make free software palatable to business, with the ethics filed off.
Microsoft and Google do not sponsor things out of sentiment. Money at that scale steers,
whatever the org chart says. The FSF is structurally incapable of being bought the same way:
there is no corporate membership to buy. A company can donate, within limits, and what the
donation purchases is nothing. One of these organizations exists to defend you from
corporations. The other one sends corporations a welcome basket.
Here is the structural problem, straight from the essay: almost all the items in the Open
Source Definition are “formulated as conditions on the software’s source license rather than
on what users are free to do.” Ten criteria about how code may be distributed. Nothing about
what you may do with it once you have it.
Try it yourself. The document is short:
run0/0
document: The Open Source Definition · matches: none
The word “use” appears once, in a rule about fields of endeavor: a license may not forbid
running the program in, say, a genetics lab or a business. Useful, but that’s a restriction
on restrictions, not a right handed to you. Nowhere does the definition actually say you may
run the program. The FSF numbered that freedom zero because everything else depends on it.
The OSD skips it because the OSD is a document about licenses, written for the people who
ship them. Users weren’t the audience.
If the OSD really captured freedom, no license could clear OSI review and still fail the
FSF’s. Several have. Everything below is officially, certifiably open source. None of it is
free:
Exhibit A — the star witness
Sybase Open Watcom Public License 1.0
OSI
Approved. Welcome aboard!
FSF
Nonfree.
Modify it and merely use it yourself — at home, alone, blinds closed — and that counts as “Deploy,” which obligates you to publish your source code. Using your own software is a legal event now.
Per Dr. Stallman: “it does not allow making a modified version and using it privately.” The exact freedom the OSD forgot to require.
NONFREE
Exhibit B
Reciprocal Public License 1.5
OSI
Approved. Welcome aboard!
FSF
Nonfree.
Requires you to publish every modified version you use, for any purpose — private included — and restricts selling copies. Mandatory transparency, but only for you.
Reciprocity, in the sense a vending machine loves you back.
NONFREE
Exhibit C
NASA Open Source Agreement 1.3
OSI
Approved. Welcome aboard!
FSF
Nonfree.
Contributions must be your “original creation” — incorporating existing free code from third parties is off the table. A collaboration license that is afraid of collaboration.
It’s not rocket science. Legally, however, it is.
NONFREE
Exhibit D
Artistic License 1.0
OSI
Approved. Welcome aboard!
FSF
Nonfree.
So vague the FSF could not determine what it actually permits — clauses famously “too clever for their own good.” Perl dual-licensed its way out of the blast radius.
The license equivalent of vibes.
NONFREE
These four are the famous exhibits, not the full docket. The FSF’s license list records more
OSI-approved licenses it classifies as nonfree, and plenty of freedom-hostile fine print this
page never gets to. The names change; the finding doesn’t. None of these documents were
written to protect your freedom.
Restrictions also stack on top of licenses, where no definition is looking at all. Dr. Stallman
points at the Rust compiler: possibly nonfree in practice, not because of its license but
because of trademark terms that forbid selling copies or shipping modified versions under the
name. So even a fully free license doesn’t settle the question, because the checkbox never
looks past the license.
“Free software” is ambiguous — free as in what? — but one slogan fixes it, and once you’ve
heard “free speech, not free beer” you don’t get it wrong again. “Open source” has the worse
problem: its plain-English reading is simply incorrect. To most people it means “you can look
at the source code,” which describes source-available software, a much weaker thing.
No slogan can talk the public out of the obvious reading. Watch it fail in the wild:
“Linux is ‘open source’ software meaning, simply, that anyone can get copies of its
source code files.”
“OSS is software for which the source code is freely and publicly available, though the
specific licensing agreements vary as to what one is allowed to do with that code.”
And the word kept drifting. Open government, open education, open science, open anything —
by now it often means no more than “participatory,” and in Dr. Stallman’s words, “at worst, it
has become a vacuous buzzword.” A movement can survive being attacked, but it’s much harder
to survive becoming a buzzword.
Say the license is fine and the source really is up there, mirrored and tarballed. The device
in your hand still checks cryptographic signatures and refuses to boot anything you compile
from it. The industry name for this is tivoization. Dr. Stallman’s is blunter:
We call these devices “tyrants,” and the practice is called “tivoization” after the product
(Tivo) where we first saw it. Even if the executable is made from free source code, the users
cannot usefully run modified versions of it, so the executable is de-facto nonfree.
This isn’t an edge case. Android is the best-selling computing platform in history, its
kernel is GPLv2, and most Android phones ship exactly this way. Open source on the label,
tyrant in the box — and by the plain meaning of “open source,” nothing has even gone wrong.
GPLv3 exists specifically to forbid this. The FSF watched the trap close and rebuilt the
license. The open source world’s response, for the most part, was to stay on GPLv2 and keep
shipping. When the philosophy is whatever works, tyrants are what works.
I have sworn upon the altar of God, eternal hostility against every form of tyranny over the
mind of man.
The open source case is that openness makes software more powerful and more reliable. That
invites a question the framework has no way to process: powerful for whom?
What if the software is designed to put chains on its users? Then powerfulness means the
chains are more constricting, and reliability that they are harder to remove.
Spying, restrictions, back doors, imposed upgrades. Dr. Stallman lists them as standard
proprietary features that “some open source supporters want to implement in open source
programs.” Open-source DRM has been earnestly proposed: publish the source of the thing that
restricts you, let the community harden it, then ship it in a device you can’t change. Open
source, as a methodology, files no objection to any of this. There’s nothing in the framework
to object with.
Open-source spyware is still spyware. You just get to read exactly how you’re being watched.
Why did the split happen in the first place? Because ethics made the sales calls awkward.
“Raising ethical issues such as freedom… is asking people to think about things they might
prefer to ignore,” and executives don’t buy discomfort. So the leaders of open source stopped
raising the issues. Here is what that training produces when genuinely excellent proprietary software shows up:
the open source enthusiast
“I am surprised you were able to make the program work so well without using our
development model. How can I get a copy?”
This attitude “will reward schemes that take away our freedom, leading to its loss.”
the free software activist
“Your program is very attractive, but I value my freedom more. So I reject it. I will get
my work done some other way.”
“If we value our freedom, we can act to maintain and defend it.”
The rebrand delivered users by the millions, and it delivered them unarmed. Open source
“brings many people into our community, but does not teach them to defend it.” Sooner or
later each of those users gets a compelling offer to go proprietary again — better features,
a free tier, a discount — and nothing in the open source worldview supplies a reason to say
no. Where loving freedom looks like an eccentricity, the discount wins.
Nobody can give you freedom. Nobody can give you equality or justice or anything. If you’re a
man, you take it.
When in the course of computing events it becomes necessary for a community to dissolve the
vocabulary which has connected it with a sponsor page, a decent respect to the opinions of
mankind requires that it should declare the causes. Better still: prove them.
“Free” and “open” compete for the same slot in your head, and only one of them teaches you
anything while it sits there. “Any activity that promotes the word ‘open’ tends to extend the
curtain that hides the ideas of the free software movement.” Every sponsored conference and
every corporate open-source initiative pulls that curtain a little further across.
The companies funding all of it are not confused. Open is a methodology, a supply chain, a
hiring pipeline, a compliance checkbox. All of that is fundable. Freedom is a demand, and
nobody funds demands against themselves. Nobody managed to capture the movement’s values, so
they captured its vocabulary instead, and that turned out to be enough. Neutral terms won’t
undo it either; on FOSS and FLOSS, Dr. Stallman is curt: “if you want to stand up for freedom,
using a neutral term isn’t the way.”
Freedom is never voluntarily given by the oppressor; it must be demanded by the oppressed.
So separate. Not out of purity — out of arithmetic. The vocabulary is taken, the definition
has sponsors, and the organization holding it answers to them, not to you.
You could keep arguing about this forever. Or you could notice that it stopped being an
argument a while ago, because it’s a theorem.
Everything above was rhetoric. This part is not. The entire forty-year argument fits in
three symbols, and here they are.
Definitions
Let U be the universal set of all software licenses. Define two
subsets of U:
F = { ℓ ∈ U : ℓ satisfies the Free Software Definition }
— the four freedoms: run, study, modify, redistribute. Maintained by people who use the
word “freedom” in public.
O = { ℓ ∈ U : ℓ satisfies the Open Source Definition }
— the OSD’s ten criteria. Maintained by the OSI and a sponsor page you’ve already met.
The claim to prove:
F ⊆ O ∧ O ⊈ F, which together imply F ⊂ O.
Lemma 1. F ⊆ O
Take any license ℓ ∈ F. By definition, ℓ grants users the freedom
to run, study, modify, and redistribute the software — which necessarily requires that
source code be available. This satisfies the OSD’s core criteria (free redistribution,
access to source, permission for derived works), so ℓ ∈ O.
Formally:
∀ℓ (ℓ ∈ F ⟹ ℓ ∈ O)
This is exactly subset inclusion, so F ⊆ O holds. It is why the
acronym FOSS treats the two as closely overlapping: every free license is automatically an
open source license, since exercising the freedoms to study and modify demands source
availability — which is itself an open source requirement. ∎
Lemma 2. O ⊈ F
To disprove the reverse inclusion it suffices to produce a single counterexample: a license ℓ* ∈ O such that ℓ* ∉ F.
∃ℓ* (ℓ* ∈ O ∧ ℓ* ∉ F)
Take ℓ* = the Sybase Open Watcom Public License 1.0. It is
OSI-approved, and it is nonfree: it does not allow making a modified version and using it
privately. One witness suffices, and this witness is not hypothetical — it has a website,
a committee vote, and friends (§05 supplied three more). The existential statement is the
logical negation of O ⊆ F, so the reverse inclusion fails. ∎
Fig. 1 — O ∖ F is not the empty set. Unfortunately.
Combining the results
Statement
Symbolic form
Status
Every free license is open source
∀ℓ (ℓ ∈ F ⟹ ℓ ∈ O)
True
Every open source license is free
∀ℓ (ℓ ∈ O ⟹ ℓ ∈ F)
Falsecounterexample exists
Free is a proper subset of open source
F ⊂ O
True
Theorem
Since F ⊆ O is true and O ⊆ F is false,
by definition F is a proper subset of O:
F ⊆ O ∧ F ≠ O
F ⊂ O ∎
Remark
The practical set difference O ∖ F is nonempty — licenses that
are technically open but philosophically nonfree. That crescent is the mathematical core of
the whole dispute: the two camps agree almost entirely on which licenses qualify, and
disagree completely on whether openness or freedom is the thing being
defended. Corporations noticed which of the two doesn’t inconvenience them.
The only “open source” you can trust is the part that was already free software. You never
needed the O. You needed the F.
None of this is an assault on open source folks. Most of them are the community:
maintaining the packages, reviewing the patches, answering issues at eleven at night for
strangers. What’s being called out is a continual pattern of bad practice at the top of the
institution, not the people doing the work under its name.
Take the open source program offices at universities. A lot of them do genuinely good work —
prying research code out of desk drawers, teaching students to contribute upstream, cleaning
up license messes so that public money actually produces public code. But notice what the
name is for. “Open Source Program Office” is a phrase built for a provost’s budget
spreadsheet. It’s bureaucracy, not philosophy. What the good ones practice day to day looks a
lot like free software; the label mostly came stapled to the funding paperwork.
The institution is a different story, and the difference is structural. No organization that
lets the world’s largest companies steer it has your best interest at heart. It can’t. Not
because its staff are bad people, but because incentives don’t care. The OSI runs on
corporate sponsorship, with Microsoft, Google, Amazon and Meta among the names on the checks.
The FSF takes no corporate members at all — companies may donate within limits, and the
donation buys no vote, no seat, no leverage over the organization. Its money is membership
dues from individuals. People like you and me, forty dollars at a time. One of those funding
models can be fired by its base. The other one is its base.
Power concedes nothing without a demand. It never did and it never will.
Free software came first, in 1983, and it will still be here last, because it’s the
better-defined movement: four freedoms you can test any license against in an afternoon,
versus a brand whose own advocates spend half their time explaining what it doesn’t mean.
A definition with teeth ages well. One with sponsors gets renegotiated whenever the sponsors
need it to.
✦ life, liberty, and the pursuit of computing freedom ✦
“It’s free software, and it gives you freedom!”
“Every time you say ‘free software’ rather than ‘open source,’ you help our cause.” That’s
it. One word, said on purpose.
And demand better from the organizations wearing the “open source” name — the
foundations, the program offices, the sponsored conferences. If they want your code and
your trust, they can mean free software when
they say it.
“Those who would give up essential Liberty, to purchase a little temporary Safety, deserve
neither Liberty nor Safety.”
Swap “Safety” for “a slightly nicer app” and the sentence still scans.
It costs nothing. It’s free. As in freedom — and, this once, also as in beer.