It is my view that plagiarism is a fact about the relationship between two texts, not the intention of an author or the process by which a text is made. Plagiarism can result from simple carelessness, which should embarrass the author, or from sheer mendacity, which the author should be ashamed of. The primary offence is not, in my view, to the original author whose work was plagiarised, but to the reader, who is being misled about the nature of the work before them and the works that are talked about in it.
It is important to publicly correct instances of plagiarism, especially in work that is influential. This is the main reason to discuss cases openly, as I do on occasion on this blog. Where it is possible to easily determine the facts, i.e., what appears on the pages of the two works involved, we should no more worry about "due process" or making "serious allegations" than we would when we criticise a writer for misreading Hegel or Lacan or, of course, Zizek. After making our concerns public, we can, of course, discuss them, and it is possible that the concerns turn out to be unjustified. As long as we make our claims with reference to the passages involved, all is well. Our readers are free to make up their minds.
Robert Sinnerbrink, for example, has said that Judith Butler "unjustly criticised Žižek for lapsing into a crude pre-Kantian ‘transcendental realism’ concerning the status of the Lacanian Real" (IJZS 2(2): p. 9). Similarly, I have said that Zizek failed to properly credit Jean-Marie Muller for the words and ideas he presents in Violence. I believe that proper sourcing would affect our reading of the passage and, indeed, undermine Zizek's claim that Muller is simply trading in "pre-modern Aristotelianism" and "ideological commonplaces". I suppose Butler could, as Zizek did with Muller, claim that her critique was altered by her publisher before publication and that she never meant to suggest that Zizek was crudely pre-Kantian. But this would still suggest something troubling, namely, that care was not taken in checking the galleys before publication.
The paragraph about the limits of desire is only one part of my critique of Zizek's use of Muller's "Non-Violence in Education". I think he present this text in a way that wildly distorts its meaning and, I suspect, its ideological function (I'm still working on that issue). Looking at Zizek's analysis, alongside the passages that he apparently self-plagiarised to produce it, suggests a very slapdash engagement with Muller's, to my mind, thoughtful essay. What Zizek has done is at least as "unjust" as what Butler may have done to Zizek, the major difference being that in order to show this it was necessary to bring to light at least one act of simple plagiarism, and another of less simple, but still problematic, patchwriting.
One of the frustrating things about finding an instance of plagiarism embedded in a passage one is already critical of is that it muddles the critique to point it out. And yet there is no way around pointing it out. The muddle is obvious from Eugene Wolters' closing remark in his dismissive post about the discovery this case:
So gross academic dishonesty? Probably not. Carelessness? Probably. What do you expect from a guy who has put out at least 3 books this year alone?
Whether or not this is an example of "gross academic dishonesty" is not the issue. (This is why it's so important to keep intention out of it.) I do, however, think we can raise questions about Zizek's basic intellectual decency, as I also did in the case of his assisted plagiary of a review of Kevin MacDonald. Like his treatment of movies he hasn't seen as examples of the ideologies he wants to critique, Zizek is here using texts that actually argue for their positions as though they are merely ideological proclamations. In the case of MacDonald, to whom he attributes a "new barbarism", he admits that he did this without reading MacDonald at all, relying on a friend's summary. In the case of Muller, his reading is so at odds with what actually happens in Muller's text that it's hard to know what was going on when he made those pages. The only charitable thing to assume is that he didn't read it very carefully.
That is, Wolters may be right that we haven't here caught Zizek trying intentionally to pass of Muller's ideas as his own (which I take it is what he means by "gross academic dishonesty"). It is sufficient that this is an instance of carelessness resulting from being way too busy getting published and not busy enough actually trying to understand the world in which we live. That's what I take away from this. Some people may not think of that as a reason to pay less attention to Zizek and pay more attention to other things. But at least now we have a more informed basis on which to make such a decision. For that reason, I am grateful to Nancy Porter for going public with her discovery.
It's also why I spend so much time talking about it. It helps us to read Zizek more accurately. It lets us form more justified beliefs about Zizek's more or less crude lapses into transcendental realism or idealism or ideology or whatever we think people should stay away from. Plagiarism obscures important facts from view. Correcting it brings them to light.