Written by: Vitalik Buterin
Translated by: Saoirse, Foresight News
In the field 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 obtain, use, and redistribute that content without restrictions, as long as they comply with the minimum rule of attribution;
If content is published under a copyleft license (such as CC-BY-SA, GPL), anyone can also obtain, use, and redistribute copies without restrictions, but if they create and distribute derivative works by modifying or combining with other works, the new works must be released under the same license. Additionally, the GPL requires any derivative works to publicize their source code and several other requirements.
In short: permissive licenses allow free sharing with everyone, while copyleft licenses only share with those who are also willing to share freely.
Since I understood things, I have always been a fan and developer of free and open-source software and free content, keen on building things that I believe are useful to others. In the past, I preferred permissive licensing models (for example, my blog is under the WTFPL license), but recently I have gradually shifted towards supporting the copyleft model. This article will explain the reasons for this shift.
WTFPL advocates a concept of software freedom, but it is not the only paradigm.
Why I once preferred permissive licenses
First, I want to maximize the adoption rate and dissemination scope of my works, and a permissive license clearly states that anyone can create based on my work without worrying about any restrictions, which conveniently facilitates this. Companies are often unwilling to open-source projects for free, and I know I lack the power to push them entirely towards the free software camp, so I want 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 sharing data fragments privately between two people should be considered a crime against a third party. They have neither interacted with nor deprived any rights from a third party (it should be noted that 'not paid' is different from 'theft'). Due to various legal factors, clearly placing works in the public domain is operationally quite complex. A permissive license is the purest and safest way to come as close as possible to a state of 'not claiming copyright'.
I truly appreciate the idea of copyleft 'using copyright to control copyright'; I think it is a clever legal concept. In a sense, it resonates with the liberalism that I advocate 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 philosophy, I often see it as a way to tame humanity's aversion to harmful reflexes, elevating freedom itself as sacred and making any act that taints freedom a detestable existence. 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, in principle, history provides many precedents showing that aversion to copyright and the practice of 'using copyright to control copyright' can coexist.
However, although the copyleft of textual works meets this definition, the copyright of GPL-style code has transcended the minimalist concept of 'using copyright to control copyright': it uses copyright for the aggressive purpose of 'forcing the public disclosure of source code'. Though this action is driven by public interest rather than selfishness in seeking licensing fees, it still constitutes an aggressive use of copyright. For stricter licenses like AGPL, this situation is even more pronounced: even if derivative works are only provided through software as a service (SaaS) and never disclosed, they are still required to publicize their source code.
Different types of software licenses set different conditions for the sharing of source code for derivative works. Some licenses require the source code to be publicly available in broad scenarios.
Why I now prefer copyleft
My shift from favoring permissive licenses to supporting copyleft stems from two major industry transformations and a philosophical shift.
First, open source has become mainstream, making it more feasible to promote companies to embrace open source. Nowadays, many companies 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; the reliance on open source in emerging fields like artificial intelligence and cryptocurrency has exceeded that of any previous industry.
Secondly, competition in the cryptocurrency field has become increasingly fierce and profit-driven, so we can no longer simply expect people to open source out of goodwill. Therefore, promoting open source cannot rely solely on moral appeals (such as 'please open the code'), but also needs to leverage the 'hard constraints' of copyleft, allowing code access only to developers who are also open source.
If we want to visually present how these two forces enhance the relative value of copyleft, it would roughly look like this:
In situations that are neither completely unrealistic nor necessarily feasible, the value of incentivizing open source is most prominent. Nowadays, mainstream enterprise sectors and the cryptocurrency industry are in this state, greatly enhancing the value of incentivizing open source through copyleft.
(Note: The horizontal axis represents the motivation level to switch to open source, and the vertical axis represents the probability of open sourcing. The comparison of the two graphs shows that the motivation and effects of promoting open source through copyleft in mainstream fields are easier to synergize, while the cryptocurrency field reflects diminishing marginal returns due to ecological maturity, indicating that the value logic of copyleft incentivizing open source changes with industry development.)
Third, Glen Weyl's economic theory convinces me that in the presence of super-linear scale returns, the optimal policy is not a strict property rights system like Rothbard/Mises. On the contrary, the optimal policy indeed requires some degree of active promotion of projects to make them more open than they originally were.
Fundamentally, if we assume that economies of scale exist, simple mathematical reasoning makes it clear that a non-zero level of openness is the only way to avoid the world ultimately falling under the control of a single entity. Economies of scale mean that if my resources are twice as much as 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...
Left graph: Proportional growth model, slight differences in the initial stage still maintain a small gap; right graph: Economies of scale growth model, slight differences in the initial stage evolve into a huge gap over time.
From a historical perspective, the key factor in curbing this trend of imbalance is that humanity cannot escape the diffusion effect of progress. Talent carries ideas and skills between enterprises and nations; poor countries can achieve catch-up growth through trade with rich countries; industrial espionage is common, making it difficult for innovation to be absolutely monopolized.
However, in recent years, multiple trends have threatened this balance while weakening traditional factors that curb imbalanced growth:
Technological progress is accelerating at an exponential rate, with the speed of innovation and iteration far surpassing previous levels;
Political instability both within and between countries has intensified: if the mechanisms for protecting rights are well-developed, the rise of others does not directly pose a threat; however, in an environment where coercive actions are more likely to occur and difficult to predict, excessive dominance by a certain entity can become a substantive risk. Meanwhile, governments around the world are less willing to regulate monopolies than before;
Modern hardware and software products possess the ability to be closed: traditional product delivery necessarily involves technological transparency (such as reverse engineering), but now closed-source products can open only the usage rights while retaining modification and control rights;
The natural limitations of economies of scale have been weakened: historically, large organizations were limited by high management costs and difficulty in meeting localized demands, but digital technologies have made ultra-large-scale control systems possible.
The aforementioned 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 enforce the diffusion of technology.
Recent policies from various governments can be seen as coercive interventions in the diffusion of technology:
The EU standardization directives (such as the latest mandatory USB-C interface) aim to dismantle closed ecosystems that are incompatible with other technologies;
China's mandatory technology transfer regulations;
The U.S. ban on non-compete agreements (I support this policy because it forces companies to achieve 'partial open source' through talent flow, although confidentiality agreements exist, there are many loopholes in actual enforcement).
In my view, the drawbacks of such policies often stem from the nature of their government's coercive policies, which leads them to prioritize incentivizing dissemination types that are heavily inclined towards local political and business interests. However, the advantage of such policies is that they can indeed stimulate a higher level of technological dissemination.
Copyleft builds a large pool of resources (code or other creative works), and these resources can only be used legally if the user is willing to share the source code of the content developed based on these resources. Thus, copyleft can be seen as a highly universal and neutral incentive mechanism for technological diffusion, which can harness the positive effects of the aforementioned policies while avoiding many of their drawbacks. This is because copyleft does not favor any particular entity and does not require a central planner to actively set parameters.
These views are not absolute. In scenarios of 'maximizing dissemination', permissive licenses still have value. But overall, the comprehensive benefits of copyleft have far exceeded those from 15 years ago. Projects that chose permissive licensing back then should at least consider switching to copyleft now.
Unfortunately, the meaning represented by the 'open source' symbol today is completely unrelated to its original intent. But in the future, we may have open-source cars, and copyleft hardware might help realize this vision.
