In the industry of free and open-source software (and more broadly, free content), copyright licenses are mainly divided into two categories:
If content is published under a permissive license (such as CC0, MIT), anyone can freely access, use, and redistribute that content without restriction, provided they adhere to the minimum requirement of crediting the source;
If content is published under a copyleft license (such as CC-BY-SA, GPL), anyone can similarly access, use, and redistribute copies without restriction, but if they create and distribute derivative works through modifications or combinations with other works, the new works must be published under the same license. In addition, the GPL also requires that any derivative works disclose their source code and several other requirements.
In short: permissive licenses allow free sharing with everyone, whereas copyleft licenses share only with those who are also willing to share freely.
Since I understood things, I have been a lover and developer of free and open-source software and free content, eager to build things I believe are useful to others. In the past, I favored permissive licensing models (for example, my blog uses the WTFPL license), but recently I have gradually shifted to support copyleft models. This article will explain the reasons for this shift.
Image source: Vitalik Buterin The WTFPL advocates a concept of software freedom, but it is not the only paradigm.
Why I used to prefer permissive licenses
First of all, I wanted to maximize the adoption rate and dissemination range of my works, and permissive licenses clearly stipulate that anyone can create based on my works without worrying about any restrictions, which precisely provides convenience for this. Enterprises are often unwilling to open source projects for free, and I realize I am powerless to push them completely into the free software camp, so I hope to avoid unnecessary conflicts with their established and unwilling-to-give-up models.
Secondly, from a philosophical perspective, I generally dislike copyright (and patents). I do not agree with the view that two people privately sharing data fragments could be considered a crime against a third party. They have neither touched nor interacted with a third party and have not deprived them of any rights (it should be noted that 'not paying' is different from 'stealing'). Due to various legal factors, explicitly releasing works into the public domain is operationally quite complex. Permissive licenses are the purest and safest way to come closest to a 'no copyright' state.
I do appreciate the idea of copyleft 'using copyright to produce copyright'; I think it is a clever legal idea. In a sense, it resonates with the liberalism I admire on a philosophical level. As a political philosophy, liberalism is often interpreted as: prohibiting the use of any violence except to protect people from violent harm. As a social philosophical idea, I often see it as a way to tame humanity's aversion to harmful reflections, venerating freedom itself as a sacred thing, making acts that tarnish freedom repugnant; even if you find the unconventional relationships between individuals uncomfortable, you cannot hold them accountable because interfering in the private lives of free individuals is itself despicable. Therefore, from a principled perspective, history provides many precedents that prove the coexistence of aversion to copyright and the practice of 'using copyright to produce copyright.'
However, although the copyleft of textual works meets this definition, GPL-style copyright for code has transcended the minimalist concept of 'using copyright to produce copyright': it uses copyright for the aggressive purpose of 'forcing the disclosure of source code.' This move, although made in the public interest rather than for private gain, still constitutes an aggressive use of copyright. For stricter licenses like AGPL, this situation is even more pronounced: even if derivative works are provided only as software as a service (SaaS) and are never disclosed publicly, they are still required to disclose their source code.
Image source: Vitalik Buterin Different types of software licenses set different conditions for sharing the source code of derivative works. Some licenses require the public disclosure of source code in broad scenarios.
Why I now prefer copyleft
My shift from favoring permissive licenses to supporting copyleft stems from two major industrial changes and a philosophical shift.
First of all, open source has become mainstream, making it more feasible for companies to embrace open source. Today, many enterprises across various industries are embracing open source: tech giants like Google, Microsoft, and Huawei not only accept open source but also lead the development of open source software; new industries such as artificial intelligence and cryptocurrency are more dependent on open source than any previous industry.
Secondly, competition in the cryptocurrency industry is becoming increasingly fierce and profit-driven, and we can no longer simply rely on goodwill for people to open source voluntarily. Therefore, promoting open source cannot depend solely on moral appeals (like 'please open source the code'), but must also leverage copyleft's 'hard constraints,' opening code permissions only to developers who are also open source.
To visually present how these two forces enhance the relative value of copyleft, it is roughly as follows:
Image source: Vitalik Buterin
In a situation that is neither completely unrealistic nor necessarily feasible, the value of incentivizing open source is most pronounced. Today, mainstream enterprises and the cryptocurrency industry are in this state, which greatly enhances the value of incentivizing open source through copyleft.
(Note: The horizontal axis represents the motivation level for shifting to open source, and the vertical axis represents the probability of adopting open source. A comparison of the two charts shows that the motivation and effect of mainstream industries promoting open source through copyleft are more synergistic, while the cryptocurrency industry, due to its mature ecosystem, is experiencing diminishing marginal returns, reflecting that the value logic of copyleft incentivizing open source evolves with industry development.)
Thirdly, Glen Weyl's economic theory convinces me: under conditions of super-linear returns to scale, optimal policy is not actually a strict property rights system like Rothbard/Mises. On the contrary, optimal policy does require a certain degree of active promotion of projects to make them more open than in their original state.
Fundamentally, if we assume the existence of economies of scale, it is clear through simple mathematical reasoning that a non-zero degree of openness is the only way to prevent the world from ultimately being controlled by a single entity. Economies of scale mean that if the resources I have are twice yours, the progress I can achieve will exceed twice yours. Thus, by next year, my resources might become 2.02 times yours, and so on...
Image source: Vitalik Buterin Left image: Proportional growth model, minor differences in the initial stage still retain small gaps; right image: Economies of scale growth model, minor differences in the initial stage will evolve into huge gaps over time.
Historically, the key factor in curbing this trend of unbalanced control is that humanity cannot escape the diffusion effects of progress. Talent carries ideas and skills when it flows between companies and nations; poor countries can achieve catch-up growth through trade with rich countries; industrial espionage is widespread, making it difficult for innovation to be absolutely monopolized.
However, in recent years, multiple trends are threatening this balance while undermining traditional factors that curb unbalanced growth:
Technological advancement is accelerating at an exponential rate, with the speed of innovation iteration far exceeding the past;
Political instability within and between nations has intensified: if the rights protection mechanisms are sound, the rise of others does not pose a direct threat; however, in an environment where coercive actions are more likely and unpredictable, the excessive strength of a certain entity becomes a substantial risk. At the same time, governments around the world are less willing to regulate monopolies than before;
Modern hardware and software products have the ability to close off: traditional product delivery is inevitably accompanied by technological transparency (such as reverse engineering), but today closed-source products can only grant usage rights while retaining modification and control rights;
The natural limitations of economies of scale have been weakened: historically, large organizations have been limited by high management costs and difficulties in meeting localization demands; digital technology has made super-large-scale control systems possible.
The above changes have intensified the ongoing and even self-reinforcing power imbalance between enterprises and nations.
Therefore, I increasingly agree that stronger measures are needed to actively incentivize or mandate technological diffusion.
Recent government policies can be seen as mandatory interventions in technological diffusion:
EU standardization directives (such as the latest mandatory USB-C interface) aim to dismantle closed ecosystems that are incompatible with other technologies;
China's forced technology transfer rules;
The US ban on non-compete agreements (I support this policy as it forces companies to achieve 'partial open sourcing' of tacit knowledge through talent flow; although confidentiality agreements exist, they are often full of loopholes in practice).
In my view, the drawbacks of such policies often stem from the nature of their government's mandatory policies, leading them to prioritize incentivizing dissemination types that are heavily inclined toward local political and business interests. However, the advantage of such policies is that they do indeed incentivize a higher level of technological dissemination.
Copyleft constructs a vast resource pool of code (or other creative works), which can only be legally used when users are willing to share the source code of the content developed based on that resource. Therefore, copyleft can be seen as a highly universal and neutral mechanism for technological diffusion that can reap the positive effects of the aforementioned policies while avoiding many of their drawbacks. This is because copyleft does not favor any specific entity and does not require a central planner to actively set parameters.
These views are not absolute. In a scenario of 'maximizing dissemination,' permissive licenses still have value. But overall, the comprehensive benefits of copyleft have far exceeded those of 15 years ago. Projects that chose permissive licenses back then should at least consider shifting to copyleft today.
Image source: Vitalik Buterin
Unfortunately, the meaning represented by the 'open source' label today is entirely disconnected from its original intent. But in the future, we may have open source cars, and copyleft hardware may help realize this vision.
This article is reprinted with permission from: (Foresight News)
Original title: (Why I used to prefer permissive licenses and now favor copyleft)
Original author: Vitalik Buterin
Translated by: Saoirse, Foresight News
The article "Has the Open Source World Quietly Changed? Why Is Vitalik Leaving Behind Permissive Licenses and Embracing Copyleft" was first published in "Crypto City"