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What are the philosophical differences between the proprietary, Open Source and Free approaches to software licensing and development?

This essay was written for a course in Open Source/Free software Philosophy & theory that I took part in at the University of Gutenberg (well, at a distance, on the internet).

This essay is released to the public under the Creative Commons Attribution-Share Alike license. This license permits free use of this work so long as attribution is given, and derivative works are released under the same license. For more information, see: http://creativecommons.org/licenses/by-sa/2.0/.


Introduction

In this essay, I want to go beyond an account of the general beliefs and attitudes of the Free Software and Open Source movements to conduct a philosophical analysis of their orientation (their goal), their logic (why they adopt their particular orientation and techniques), the limits of their space and their techniques. I will develop an understanding of the proprietary, Open Source and Free Software approaches on this basis, and then compare each approach. Given the scope of such a task, I will focus on how each approach accounts for property, community and the producer-consumer relationship, chosen because my intuition and experience suggest that they may be central themes.

Since there is no central organisation that advocates an approach that applies to all proprietary software, I will study a range of techniques commonly found. With the Open Source and Free Software approaches, I will focus my arguments on the Open Source Initiative and the Free Software Foundation respectively, with supplementary arguments from advocates who openly associate themselves with those organisations. In this way I hope to avoid confusing the terms as many academics do when conflating the approaches into one subject (e.g. discussions about ?Free Libre Open Source Software?, or FLOSS for short).

Though I enter this project as a self-proclaimed advocate of the Free Software approach, I will avoid making judgements as to which approach is better, and focus on better developing this neglected aspect of the field of Free and Open Source software. I will also endeavour to provide charitable reconstructions of each approach's orientation and logic, finding coherent arguments for three models, even if the result may not cohere with their advocates' arguments (e.g. my assertion that proprietary software has nothing to do with property rights).

In proceeding in this manner, my essay will show that there is almost no philosophical difference between the proprietary and Open Source approaches, whilst the Free Software approach is philosophically distinctive and productive (insofar as it provides a basis for further research in this area).

Proprietary Software

The orientation of proprietary software is to create good software. It's that simple. It's techniques, from a philosophical point of view, are similarly banal, involving various development methodologies and the application of copyright to protect the software from outside interference, and usually to protect the financial interests of the authors.

The logic behind this technique seems at first glance to be in the spirit of copyright: to reward the authors, and to promote future creativity such that good software is created. The reward is assumed to be financial, and proprietary software is assumed to give better rewards to the author than its alternatives. The logic suggests both that the author has a right to own his/her creation, and that by generously rewarding the author society benefits from the author's ability to create more software in the future.

It should immediately be noted that the financial nature of the reward is not necessary, nor should we assume that society will gain the consequent services of the author after paying such a reward. Proprietary software can be released for free ? as freeware ? or in the form of a time limited demonstration ? shareware ? giving the author no financial reward, or in the case of shareware, a voluntary and limited reward. In fact the scope for financial reward is shared by the Free and Open Source approaches as well.

The logic of copyright is not so clear. Traditionally property ? including physical property ? is defended in one of two ways: by reference to the inalienable right of the owner, or by reference to the benefits to society. In both cases, the crux of the argument is the justification of exclusion, such that the owner can exclude the public from using the property as he/she chooses.

Locke, for example, suggested that we have an inalienable right to own that which we have worked on. His argument was ?not that the existence of private property serves the public good, but rather that rights of private property are among the rights that men bring with them into political society and for whose protection political society is set-up" (Waldon, 1998: 137). Locke went on to explain how we can come to own physical objects such as land that were previously in the commons. By mixing our labour with that which nobody owns, we come to own that part of commons (Locke, 2003). In the context of software, by mixing my work with ideas that I discover I come to own the result; the commons can be thought of as containing undiscovered ideas, and ideas that are given by their creators to the commons, such as programming languages and techniques.

Of course in this context, Locke's argument faces a problem: in mixing my own ideas with others', I am not taking their ideas away in the same way that I might remove land from the commons by cultivating it and consequently claiming it as my own. This is because ideas aren't rivalrous or scarce, meaning that an infinite number of people could use the idea without reducing its utility. So there is no need for me to extend ownership over an idea if I can gain the same utility from it in the commons. Furthermore, in creating any software I will be drawing not just on the commons ? the languages and techniques given freely to programmers ? but also on ideas used in other people's software. So although I may claim the right to own my creation, to the exclusion of others if I wish, I would need to either pay my dues to every author upon whose work I had based my own, or I would only be able to claim rights to those parts of my work that were my own original creation.

The impracticality of this technique1 suggests the necessity for a different logic, that of copyright as a bargain for the public good. According to this argument, the public benefits from the creation of software, but authors cannot meet the public's needs without the finances to put considerable amounts of time into the work. Therefore the public grants limited property rights to the authors, which may provide financial rewards, in return for the increased future productivity of the author2.

This seems to be the logic of proprietary software. By excluding others from the source code - the instructions that a programmer understands and works with to create software ? it's technique protects the author's position as the only person who can modify the program. There is no escrow agreement on the source code, and so nothing compelling the author to release the code at any time. The software is, for all intents and purposes, a black box. Therefore the logic is that the bargain meets proprietary software's orientation ? creating good software - best when the author excludes the public from modifying his/her software, and restricts the public's rights of redistribution.

The latter point, however, doesn't apply to freeware, where the author employs the techniques of proprietary software without seeking financial reward and without restricting the public's rights of redistribution. To explain this, one must explore one other aspect of the logic of proprietary software, that of producer and consumer.

The user passively consumes the software, and though it may well enable creativity, the software itself is an immutable commodity. The immutability that is proprietary software's particular orientation isn't found in any other kind of property; all physical objects are only limited in their mutability by the technical expertise of the owner. Therefore uniquely the relationship between producer and consumer in this context allows no opportunities for productive community, be it hobbyist's clubs or businesses that will modify the software, except where the author steps outside of the proprietary norm and gives special access to the source code to particular individuals or groups. The motivations for withholding the source code can only be guessed at ? the protection of ego, of being the sole author, a lack of awareness about alternatives, and disagreement with the alternatives are reasonable candidates.

In conclusion, then, there are two features of proprietary software that are philosophically distinctive: a commitment to it's techniques as being the best way to create good software as part of the copyright bargain; and that those techniques involve the creation of a producer-consumer relationship rather than a community of equals through the application of restrictive copyright licensing.

Open Source Software

The orientation of Open Source Software is described by the Open Source Initiative as producing good software. The definition of Open Source Software is given in relation to proprietary software, comparing the techniques in terms of development methodologies and copyright licensing terms. It is the techniques that set the two approaches apart, not least because Open Source Software rejects the main premise of proprietary software licensing ? that it is better to restrict access to the source code. The logic for this difference, according to the OSI, is that ?when programmers can read, redistribute, and modify the source code for a piece of software, the software evolves. People improve it, people adapt it, people fix bugs. And this can happen at a speed that, if one is used to the slow pace of conventional software development, seems astonishing.? (OSI, 2004a)

This is achieved by subverting the traditional licensing of copyrighted works. Normally one would not think of a copyrighted work as being ?licensed?; it is simply released under terms chosen by the owner of the copyright, who reserves all rights connected with the work, which in the case of proprietary software involves at least the right to restrict the ability to modify the software. Open Source Software is released under a license that specifically grants the right to modify the software to all who would take the opportunity. The author renounces this ?right? because he/she thinks it will result in better software. The Open Source approach therefore subscribes to the same philosophical justification of property in the software context as the proprietary approach, namely that being able to own the software serves the public good. If this seems paradoxical ? that society's ability to modify the software depends upon the author(s) owning the software ? it is because an author could release software into the public domain without the source code, and be under no compulsion to do so upon request, in effect releasing proprietary software. The technique of Open Source Software is subversive because it abuses the technique of proprietary software to renounce it's logic.

However, despite the apparent challenges to the concept of intellectual property as advanced by proponents of proprietary software, Open Source advocates rely on ?economic self-interest arguments? without recourse to ?moral crusades? and ?ideological tub-thumping? (OSI, 2004d). In other words, Open Source as an approach explicitly avoids making itself philosophically distinct from proprietary software and any other intellectual property regime. Raymond even tries to fit Open Source into Locke's approach to property. Although his claim that Locke's theory was the systematisation of a thousand-year long organic development in property rights is patently false3 and his omission of Locke's account of property rights is telling, Raymond's reconstruction of Locke's arguments provide a pragmatic basis for his account of Open Source property rights that in part cohere with my reconstruction of a Lockean argument for proprietary software. It is one of hackers receiving increased yields from mixing their labour with the ideas commons, thereby claiming property rights as a pragmatic bargain with society, exactly as proprietary software conceives itself (Raymond, 1999: 93-97). The similarity is unsurprising, since Raymond's oft-stated aim is to sell the techniques of Open Source to businesses, who would be uncomfortable adopting a philosophy that threatens to undermine their existing property rights.

On these limited terms there can be no philosophical difference between the two approaches; both are based upon a particular application of copyright being the best way to produce good software. Even in the Open Source Definition, logic such as ?no discrimination against persons or groups?, which seems at odds with the logic and orientation of proprietary software, are explained in relation to their capacity to ?to get the maximum benefit from the process?, where a benefit is defined as the production of more good software (OSI, 2004b).

On community verses the producer-consumer model, Open Source advocates are a little more confusing. On the one hand, they claim that they are ?promoting the Open Source Definition for the good of the community? (OSI, 2004a) and on the other hand they claim to promote the definition on ?pragmatic, business-case grounds? (OSI, 2004c). As with the Open Source approach to property, this discrepancy can be explained in terms of technique.

By opening the source code and thereby allowing any individual to work on it, the Open Source approach rejects proprietary software's exclusion of the community. Indeed, a community of developers is seen as central to the pragmatic benefits of the approach (Raymond, 1999: 61). But true to the roots of the approach, community only matters where it provides a benefit in terms of creating better software. So a community of software developers is important but a community of end users isn't, because they provide no discernible contribution to the software that requires a community; bug reports and financial support (through sales or donations) can be done as well by atomised individuals as by communities. Thus the Open Source approach maintains a contributor-user distinction.

The Open Source Initiative maintains three central advocacy documents: one for hackers, one for customers, and one for businesses (both those producing and consuming software) (OSI 2004e; OSI 2004f; OSI 2004g). This conceptualisation of the relationships in the software context makes clear that the Open Source approach involves a producer-consumer relationship based upon its contributor-user distinction, just as the proprietary software approach does. It sees no pragmatic benefit in breaking this relationship down throughout society, nor does it seek to develop a philosophical argument for such a change. The only difference is that the Open Source approach extends the limits of the community space to encompass all potential contributors, whilst the proprietary software approach limits the community space to those individuals or groups it wants to include, on a seemingly arbitrary basis.

Free Software

The orientation of Free Software is to create good software that provides certain socially useful freedoms. It is defined in terms of ?liberty not price?, a frame of reference entirely absent from both proprietary and Open Source approaches. And crucially it is defined as an ethical orientation, not a pragmatic orientation (Stallman, 1992, 1994). According to the Free Software Foundation, the orientation is related to four kinds of freedom:

  1. The freedom to run the program, for any purpose (freedom 0).
  2. The freedom to study how the program works, and adapt it to your needs (freedom 1). Access to the source code is a precondition for this.
  3. The freedom to redistribute copies so you can help your neighbour (freedom 2).
  4. The freedom to improve the program, and release your improvements to the public, so that the whole community benefits (freedom 3). Access to the source code is a precondition for this.(FSF, 2004a)

The Free Software approach achieves this with exactly the same techniques as the Open Source approach: a range of software development methodologies based upon the free redistribution of the source code, made possible by the subversion of copyright through licensing. As Eric Raymond, a leading Open Source advocate says, ?the software, the technology, the developers, and even the licenses are essentially the same. The only thing that differs is the attitude? (Engel, 2004). The logic of the Free Software orientation is very different to that of the Open Source approach, situating itself in the realm of ethics rather than in the realm of pragmatics.

To begin with, the Free Software approach renounces the concept of software ownership. Software ownership is unethical, the leading figure of the Free Software movement ? Richard Stallman ? often declares. In contrast to Raymond's omission of natural property rights in his attempt to lend a Lockean justification to property, Stallman explicitly rejects this notion, though without reference to Locke or any other natural right theorists. Rather, in typical American style, he uses the position of the US constitution, which describes the copyright bargain, as precedent for his position. Property rights, he asserts, require a social justification, and in the case of software there can be no such justification, therefore ownership of property is unethical (Stallman, 1992). Thus, from a different orientation, the Free Software and Open Source approaches share a certain logic ? of socially justified property rights ? that is in opposition to that of proprietary software ? of natural property rights.

Stallman judges the social justification on grounds of collectivist consequentialism rather than principle by examining the consequences of ownership on the developers, in terms of how ownership restricts their freedom to develop good software, and on the users, in terms of how ownership restricts their freedom to use the software in particular ways. He proceeds on a basis of comparative harm, asking if the harms resulting from the restrictions advocated by the proprietary approach outweigh the harms resulting from the freedoms advocated by the Free Software approach (Stallman, 1992), and advocates a kind of rule utilitarianism that says: the (social) utility of always sharing software under a Free license outweighs any harms, thus it is an ethical duty to always do so.

Any form of rule utilitarianism needs a list of objective values against which it can judge an issue. Ram tries to provide such a list by describing three harm principles: First, that copying and modifying software doesn't harm anyone, including the original author, since they lose nothing in the process; second, that restricting the ability of society to copy and modify software harms progress; third, that restricting the ability of society to copy and modify software abridges society's freedom of expression and thought, because one is unable to access the source code and then express the information within (Samudrala). Free Software advocates claim that the resulting harm principle ? that there is less harm and more social utility in the Free Software approach than in the proprietary approach - can be taken as the ethical basis for their orientation.

With this ethical basis in mind, one can develop a similar understanding of the Free Software approach to the producer-consumer versus community models. As with Open Source, an obvious consequence of the techniques of the Free Software approach is that you are able to work in a community of developers. In contrast to the Open Source approach, however, Stallman says that you ?deserve to be able to cooperate openly and freely with other people who use software? (Stallman, 1994); this can be interpreted as making an ethical claim about the right of an individual to work in a community based upon a rule of social utility. This claim, however, still only applies to developers; although Stallman mentions ?people who use software?, he doesn't provide a means of extending the limits of this community beyond those who are able to work with the developers, i.e. developers themselves.

The Free Software approach takes this claim further by ?[encouraging] the spirit of voluntary cooperation? (Stallman, 1994), regardless of the field of endeavour. By using certain techniques, and respecting the rights of others to work in communities, the Free Software approach encourages similar practices elsewhere and thus extends the limits of its space to to all information-based work. Not sharing information freely, the approach claims, is a betrayal of our social obligations (Stallman, 1992). But even so, this approach still creates a producer-consumer relationship insofar as there will be, in any field of endeavour, those who work on a set of information and those who use it. Advocates of the Free Software approach have two moves open to them at this point: one can either claim that this relationship is natural and unproblematic, or one can claim that the Free Software approach weakens, and perhaps even promises to eradicate, the relationship.

The first move is philosophically uninteresting, an acknowledgement and legitimisation of the status quo4. That is not to say that it is wrong or logically incoherent with the Free Software approach, but that nothing more needs to be said on the matter for the purposes of this essay. The second move can be made most simply by extending the ?spirit of cooperation? argument to suggest that by encouraging this spirit, consumers are empowered ? both in terms of the software they have and their psychology ? and thus more likely to engage with the producers in a way that can't be characterised as consuming. Communities who customise or localise their software like KDE-Farsi and GNOME-Bengali are good examples of how this might take place, as are communities and cooperatives that are set-up to manage the spread of Free Software, such as in Venezuela and Brazil (Chance, 2004). Users, who with proprietary software would have simply consumed the software, are able to use it in a community context, and in so doing develop new and strengthen existing communities based not around software development, nor even necessarily software use (it may be an ancillary concern for the community).

In conclusion, then, the Free Software approach is philosophically distinctive because, in contrast to both the proprietary and Open Source approaches, it is based on an ethical claim about the absolute importance of social utility, and about the relative social utility of different legal and development techniques. The approach rejects both natural rights and social bargain arguments for property in the software context, and subverts copyright law to create a global commons of software. Notions of community and cooperation are also central to the approach, both within the development community, amongst users, and between the two.

Beyond Free Software?

The Free Software approach does not stop there, however. I make an artificial pause in my essay because strictly speaking what follows is not, according to the methodology I described in my introduction, to be considered part of the Free Software approach, since the ideas are not expressed by the Free Software Foundation. Nevertheless, they can be taken as logically consistent extensions of the approach, and give us insight into both it's nature and significance. Moreover, though the Free Software approach is obviously not limited to software, but applicable in part to any field of endeavour in which there is more social utility than harm in renouncing property rights and freely sharing in communities, it will only be in part because the techniques and the limits of space will most probably differ.

The most ideologically congruent approach to have emerged from the Free Software social movement is the Creative Commons community, whose orientation is to create good cultural objects that provide useful social freedoms. The community's technique consists of licenses for all kinds of cultural objects (including kind of audio, images, text and video) that are analogous to those used by the Free Software approach. The central organisation also provides a logic for advocacy, with a periphery of individuals and (for the most part) loosely connected groups who employ and promote the orientation, logic and techniques of the community. Though not as radical as the Free Software Foundation, which claims that all software should be developed and distributed according to its approach, Creative Commons does base its logic upon a slightly diluted version of the Free Software Foundation's ethical claim: that where it promotes more social utility than harm, it is more ethical to employ the organisation's techniques, and there is significant social utility in a vibrant commons of Free information. Finally, though Creative Commons states that it has no disagreement with owning information, it's logic of ?some rights reserved? rather than ?all rights reserved? being a better technique to support the creation of cultural objects for the good of society does suggest the same ethical spirit as the Free Software approach (Creative Commons; Lessig, 2003: 276-278, 285-286).

A far more radical extension of the Free Software approach can be seen in the work of many contemporary Marxist and Marxian theorists. Though this has been greeted with howls of despair from many, especially Open Source Advocates ? Eric Raymond talks of ?Communistic flake cases? undermining the movement without even referring to these theorists (Engel, 2004) ? the links between the Free Software approach's renunciation of property and the creation of an information commons, and Marx's theories of value, property and labour relations are compelling.

According to Marxist theory, capitalism depends upon a particular mode of production that reduces the labour value of objects (the work that went into them) to an exchange value (their price). By abstracting all products from the conditions of their creation, capitalism creates a market of commodities that depends upon a competitive relationship between producers, and a passive one-way relationship between producer and consumer (the producer creates something whilst the consumer only returns abstract exchange value). The Free Software approach is contrary to this system, because it is based upon labour value ? how good the software is ? and doesn't even account for exchange value, though it doesn't preclude it. Though Free Software is traded as a market commodity already, some Marxian5 theorists contend that Free Software cannot be considered a commodity since, under the terms and spirit of the GPL, it will eventually be released free of charge, and it is produced not for its exchange value but for its labour and use value (Merten, 2004).

It is unclear whether or not adopting the Free Software approach makes you a Marxist; that much requires further study, and will probably never be agreed on for lack of definitive statements from the FSF on the matter (i.e. both Marxists, liberal capitalists and individuals of other ideological persuasions will find reasons to reinterpret the approach in their favour). Regardless, the fact that Creative Commons was inspired by the Free Software approach, and that Marxian theorists and liberal capitalists alike find productive ideas in the approach, both suggest that it is philosophically substantial beyond the context of software.

Conclusion

In this essay I set out to develop an understanding of the proprietary, Open Source and Free Software approaches to software development and licensing, with particular attention paid to how they account for property, community and the producer-consumer relationship. I have shown that both the proprietary and Open Source approaches share the orientation of creating good software; they both respect the importance of property as a technique, though Open Source widens the limits of the space in which property doesn't apply to include an open community of developers; both approaches ultimately uphold the consumer-producer relationship, though Open Source significantly weakens it. And neither make any philosophical claims about their approach, suggesting that they are ideologically congruent with the dominant ideology of our time.

The orientation of the Free Software approach is to create socially useful software, which is defined in terms of certain freedoms. As part of this orientation, the approach rejects not only the importance but also the ethical status of property, and declares that as a rule, all software should employ the Free Software approach. Though, as with Open Source, the approach only operates within the limits of the developer communities, it promotes the spirit of community and cooperation whilst providing considerable opportunities for communities to develop around its products. Thus the approach rejects the centrality of the producer-consumer relationship, replacing it as far as possible with empowered communities.

Both the Open Source and Free Software approaches share the same techniques. But their orientation, logic and the limits of their space are radically different. Raymond best summed it up when he launched the OSI; Open Source is an attempt to capitalise on Free Software's techniques, leaving Free Software advocates to advance more radical critiques of contemporary approaches to property, community and the producer-consumer relationship.

References

T. Chance (2004). In defense of Free Software, community, and cooperation, Tom Chance's Web Site, https://tomchance.org.uk/writing/free-sw-community, on file with author

Creative Commons (Date unknown). Frequently Asked Questions, Creative Commons Web Site, http://creativecommons.org/faq, on file with author

A. Engel (2004). Free as in Freedom - Part Two: New Linux, Press Action Web Site,http://www.pressaction.com/news/weblog/full_article/engel12122004/, on file with author

FSF (2004a). The Free Software Definition, Free Software Foundation Web Site, http://www.fsf.org/philosophy/free-sw.html, on file with author

L. Lessig (2003). Free Culture: How Big Media Uses Technology and the Law to Lock Down Culture and Control Creativity

J. Locke (2003). Second Treatise of Government, in Locke: Two Treatise of Government, ed. P. Laslett

S. Merten (2004). Gnu/Linux - Milestone on the Way to the GPL-society version 4, Open Theory Web Site, http://www.opentheory.org/gplsociety/text.phtml, on file with author

OSI (2004a). Open Source Initiative ? Welcome, Open Source Initiative Web Site, http://www.opensource.org, on file with author

OSI (2004b). The Open Source Definition, Open Source Initiative Web Site, http://www.opensource.org/docs/definition.php, on file with author

OSI (2004c). History of the OSI, Open Source Initiative Web Site, http://www.opensource.org/docs/history.php, on file with author

OSI (2004d). Frequently Asked Questions, Open Source Initiative Web Site, http://www.opensource.org/advocacy/faq.php, on file with author

OSI (2004e). Open Source Case for Business, Open Source Initiative Web Site, http://www.opensource.org/advocacy/case_for_business.php, on file with author

OSI (2004f). The Open Source Case for Customers, Open Source Initiative Web Site, http://www.opensource.org/advocacy/case_for_customers.php, on file with author

OSI (2004g). The Open Source Case for Hackers, Open Source Initiative Web Site, http://www.opensource.org/advocacy/case_for_hackers.php, on file with author

E. Raymond (1999). The Cathedral & The Bazaar: Musings On Linux and Open Source by an Accidental Revolutionary

R. Samudrala (Date unknown). A primer on the ethics of "intellectual property", Ram Samudrala's Web Site, http://www.ram.org/ramblings/philosophy/fmp/copying_primer.html, on file with author

J. Soderberg (2002). Copyleft vs. Copyright: A Marxist critique, In First Monday, volume 7, http://firstmonday.org/issues/issue7_3/soderberg, on file with author

J. Soderberg (2004). Reluctant revolutionaries - the false modesty of reformist critics of copyright, In Journal of Hyper(+)drome.Manifestation issue 1, http://journal.hyperdrome.net/issues/issue1/soderberg.html, on file with author

R. Stallman (2001). Free Software: Freedom and Cooperation, Transcript of talk on Free Software Foundation Web Site, http://www.fsf.org/events/rms-nyu-2001-transcript.txt, on file with author

R. Stallman (1992). Why Software Should Be Free, Free Software Foundation Web Site, http://www.fsf.org/philosophy/shouldbefree.html, on file with author

R. Stallman (1994). Why Software Should Not Have Owners, Free Software Foundation Web Site, http://www.fsf.org/philosophy/why-free.html, on file with author

J. Waldon (1988). The Right to Private Property

Notes

1 This technique is in practice in the US, and being proposed by some in the EU, in the form of software patents. I assume in this essay that the practice isn't coherent with the orientation of creating lots of good software.

2 This bargain is described by the US constitution, for example, as a means ?to promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their? creations.. It should be noted that there is considerable controversy over the nature of the exclusive right, and over the length of time for which they apply

3 In fact, Locke was trying to undermine the long-held divine right of the English monarchy and give property rights for the first time to wealthy landowners, with religious justification

4 Here I take the status quo to mean the particular form of liberal capitalism that is the dominant ideology of our time, which requires this kind of producer-consumer relationship. Going into this claim is beyond the remit of this essay, so I will leave it at that.

5The distinction between ?Marxist? and ?Marxian? is subtle; the latter simply inherits some of Marx's theories without necessarily agreeing with all of his work