Dennis Hackethal's Website, Veritula, Is Worse than Plagiarism

Dennis Hackethal created a website, Veritula, based on my philosophy, Critical Fallibilism (CF). He explains and uses CF ideas but, instead of crediting the ideas to me or CF, he credits them (without evidence or citations) to Karl Popper's philosophy, Critical Rationalism. This is quintuply problematic:

• He's using my ideas without giving me credit.
• He's implicitly accusing me of plagiarizing Karl Popper.
• He's spreading misinformation about what Popper's views were.
• The misinformation attributes ideas to Popper that many people see as weird, bad or false.
• He's implying that David Deutsch and other Popperians misunderstood Popper, without giving evidence, quotations or citations.

Extensively using CF ideas and misattributing them to Popper is worse than plagiarism. In addition to using my ideas without crediting me (the same harm plagiarism does), he's also implying that I'm a plagiarist, implying that other people misunderstood Popper, confusing people about Popper's views, and falsely attributing unpopular ideas to Popper (extra harms that merely plagiarizing me wouldn't cause).

Creating CF took over 10,000 hours of largely unpaid effort while I worked other jobs, outside of philosophy, to support myself. I share CF ideas hoping people will learn from them or critique them. While CF isn't very popular, if someone actually likes my ideas enough to study them, I don't want to be plagiarized or misattributed.

I wrote an article using Popper quotes to show that CF's distinctive ideas aren't plagiarized from Popper. Popper actually contradicted them.

This article presents evidence that Hackethal is using CF ideas, without crediting CF, by comparing Hackethal quotes with my essays. Previously, Hackethal hired me to help teach him about philosophy, so I also provide quotes from teaching calls and documents.

Some examples I provide are important on their own. Others wouldn't be a big deal alone but contribute to a broader pattern.

Context

In 2020, I accused Hackethal's book of plagiarizing me. Years later, he made long, error-filled blog posts and videos attacking me. He's threatened me with a lawsuit and offered to give other people money to help them sue me. He falsely tells people I'm a cult leader. He's published photos of me while calling me dangerous. He's hired private investigators. He spends a lot of time reading my writing and he won't leave me alone. I created a timeline.

The strangest part of the timeline is a four year gap between events. I thought Hackethal had moved on, but then he started attacking me much more vigorously than before over old issues.

Although Hackethal has been trying to ruin my reputation, I only responded minimally seven months ago. I've let many lies go unchallenged. I didn't understand why he started doing it four years later, and I didn't want to engage. Now I see a potential motive: it benefits him if it looks like my criticisms of Veritula are just revenge for his attacks on me. It benefits him to discredit me so that people don't listen to me. If people have a dismissive attitude to me, then he can get away with using my ideas without crediting me. Creating a big, messy fight between us can distract people from his plagiarizing me in A Window on Intelligence: The Philosophy of People, Software, and Evolution – and Its Implications and doing even worse with Veritula. Please remember that I said nothing for the last seven months; I have a thick skin and this post is an evidence-based attempt to set the record straight.

Technically Not Plagiarism?

Plagiarism means taking credit for other people's ideas. Hackethal is using my ideas but crediting them to a third party, which may be a way to avoid additional plagiarism accusations on a technicality.

The 1913 version of Webster's Dictionary defines "plagiarize" as "To steal or purloin from the writings of another; to appropriate without due acknowledgement (the ideas or expressions of another)." Using CF ideas without crediting CF qualifies under this definition of plagiarism. But other dictionaries require that the plagiarist takes credit themself.

Sometime after I accused his book of plagiarism, Hackethal "avoided Temple’s blog for years". He says he was trying to prevent accidental plagiarism. It's also a good way to prevent intentional plagiarism or misattributing my ideas to Popper. But then he decided to start reading my essays again (he doesn't say why). Then he started attacking me and made Veritula.

Veritula Uses CF Ideas without Crediting CF

Blockquotes are from Hackethal's How Does Veritula Work? (mirror). Italics are in the originals; bold is added for this article unless indicated.

Veritula is a programmatic implementation of Popper’s epistemology. [bold in original]

It [isn't Popper's epistemology](#). As we'll see below, it implements CF ideas like decisive criticism, binary evaluations of ideas, and debate trees.

Because decision-making is a special case of, ie follows the same logic as, truth-seeking, such trees can be used for decision-making, too.

The idea of using epistemology for decision-making is found on the Critical Fallibilism homepage and in my Yes or No Philosophy, Introduction to Critical Fallibilism, Multi-Factor Decision Making Math, Introduction to Theory of Constraints ("This is related to decision making in general."), Critical Fallibilism and Theory of Constraints in One Analyzed Paragraph and Academic Literature for Multi-Factor Decision Making.

If an idea, as written, has no pending criticisms, it’s rational to adopt it and irrational to reject it. What reason could you have to reject it? If it has no pending criticisms, then either 1) no reasons to reject it (ie, criticisms) have been suggested or 2) all suggested reasons have been addressed already.

If an idea, as written, does have pending criticisms, it’s irrational to adopt it and rational to reject it – by reference to those criticisms. What reason could you have to ignore the pending criticisms and adopt it anyway?

Now, [the idea] is considered unproblematic again, since [its criticism, which has now been counter-criticized] is problematic and thus can’t be a decisive criticism anymore.

‘Has pending criticisms’ vs ‘has no pending criticisms’

Veritula therefore also enables you to hold irrational people accountable: if an idea has pending criticisms, the rational approach is to either abandon it or to save it by revising it or addressing all pending criticisms.

Don’t worry about which ideas are better than others. [...] Only go by whether an idea has outstanding criticisms. [source, mirror]

Introduction to Critical Fallibilism: "CF says all ideas should be evaluated in a digital (specifically binary) way as non-refuted (has no known errors) or refuted (has a known error)."

Critical Fallibilism homepage: "Critical Fallibilism (CF) is a rational philosophy which explains how to evaluate ideas using decisive, critical arguments and accept only ideas with zero refutations (no known errors)."

Compared to some recent CF essays, Hackethal slightly rewords some points and uses synonyms ("outstanding criticism", "pending criticism", "unproblematic"). I've used those terms too, e.g. "outstanding criticism" is in Rationally Resolving Conflicts of Ideas, Judging Experts by the Objective State of the Debate, Paths Forward or Prediction Markets? and my discussion with Aubrey de Grey.

More important than the wording is the concept. Hackethal is talking about evaluating ideas in a binary way as non-refuted or refuted. He's basing refutation on even one non-refuted criticism. This is one of CF's main ideas which will be discussed more throughout this article. It's still the same idea even if you call non-refuted criticisms "pending" and call refuted ideas "problematic".

Hackethal also used CF's exact term "decisive criticism". He may be so immersed in studying CF that he doesn't realize how unique this term is to CF. Google searching "decisive criticism", the top two results, AI summary and sidebar (AI sources) are all CF material:

Would I give each idea a slider where people can say how ‘good’ the idea is? What values would I give the slider? Would the worst value be -1,000 and the best +1,000? How would users know to assign 500 vs 550? Would a ‘weak’ criticism get a score of 500 and a ‘strong’ one 1,000? What if tomorrow somebody finds an even ‘stronger’ one, does that mean I’d need to extend the slider beyond 1,000? Do I include arbitrary decimal/real numbers? Is an idea’s score reduced by the sum of its criticisms’ scores? If an idea has score 0, what does that mean – undecided? If it has -500, does that mean I should reject it ‘more strongly’ than if it had only -100? And so on.

Criticizing score systems is a main point of CF. It's found in my Introduction to Critical Fallibilism, Yes or No Philosophy and Score Systems, Yes or No Philosophy (paid educational product), Yes or No Philosophy Summary (which has links to many other relevant essays), and Multi-Factor Decision Making Math.

In my understanding, Popper’s epistemology [...] does not assign strengths or weaknesses.

It's a core CF idea, repeated in many essays, to not evaluate how strong or weak ideas are. E.g. Introduction to Critical Fallibilism: "CF’s most important original idea is the rejection of strong and weak arguments." This is what my Yes or No Philosophy material is about.

It's [false that Popper avoided strength and weakness](#) like CF does.

If [the proponent of an idea] fails to address even a single criticism, the idea remains problematic and should be rejected.

If you can think of neither a revision of [an idea] nor counter-criticism to [a criticism of that idea], your only option is to accept that [that idea] has been (tentatively) defeated. You should therefore abandon it, which means: stop acting in accordance with it, considering it to be unproblematic, etc.

And (from Hackethal's Twitter):

4. Re decisiveness of criticism [bold in original]

[...] any criticism, no matter how small, is decisive if left unaddressed.

I've covered the issue of not discounting "small" criticism repeatedly, e.g. in Ignoring “Small” Errors and “Small” Errors, Frauds and Violences.

The main idea in these quotes is that criticism is decisive: it only takes one (non-refuted) criticism to refute an idea so that we should reject it. This is a core CF idea repeated in many essays, e.g. Introduction to Critical Fallibilism: "Criticisms should be decisive, rather than merely saying an idea isn't great. That means you don't accept both the criticism and its target because they’re incompatible".

I also discussed this with Hackethal on a call. And there was also a section titled "All Criticisms Are Decisive" in a confidential CF document I sent Hackethal in 2019. I'll provide details in the "Teaching Calls" and " Confidential Documents" sections below.

Any criticism no matter how small destroys its target decisively if unaddressed. Whether or not its decisive is determined by whether or not there are any counter-criticisms, not by assigning some strength score (a remnant of justificationism). A criticism is decisive as long as there are no counter-criticisms. In the absence of counter-criticisms, how could it not be decisive? [source, mirror]

This uses my decisive criticism idea again and my point about "small" criticism. It also refers to the "target" of a criticism. I used that "target" language in Introduction to Critical Fallibilism.

I said that scores are a form of justificationism in Kialo and Indecisive Arguments and other essays.

Also, decisiveness and refutation status are different things. A criticism is decisive if it contradicts its target so they can't both be correct. A criticism refutes a target if it's both decisive and non-refuted. A successful counter-criticism makes a criticism refuted, not indecisive. While Hackethal is recognizably copying CF, he's also introducing some errors.

That’s a fair concern if you’re talking about duplicate criticisms, which public intellectuals do field. The solution here is to publicly write a counter-criticism once and then refer to it again later.

I called this a "library of criticism" in Yes or No Philosophy. Hackethal calls Veritula a "dictionary for ideas". The "dictionary" keeps track of ideas and lets people refer to them again later so that they don't "have same [sic] discussions over and over again". My "library of criticism" also let people "refer" to "counter-criticisms [and regular criticisms] ... again later".

I've also talked about this repeatedly in my many essays ("Thinkers should write reusable answers to arguments") on Paths Forward ("You can reuse answers that were already written down in the past, by you or others." and "Most bad ideas get pretty repetitive. People will keep bringing up the same points over and over. That’s fine. They don’t know better. You can deal with it by answering the issue once, then after that refer people to your existing answer.").

If you’re talking about new criticisms, however, I think you should address and not dismiss them.

This is also in my original Paths Forward essay: "If there are good ideas already written down (or in any format which allows reuse), then you can save lots of time. If there aren’t (reusable) answers yet, then the issues people are raising are worth taking some time to answer properly."

My Paths Forward Summary makes this point too: "In general, either an issue has been answered before or else it’s worth the time for someone to answer it."

Discussion trees

This is a distinctive CF term. Maybe Hackethal has studied CF so much that it seems like a normal term to him, not a recognizable part of CF. On Google, searching for discussion trees, the only relevant result is my essay Discussion Trees; the rest of the results are for decision trees. And searching discussion tree, Google automatically gives results for decision tree.

Since there can be many criticisms (which are also just ideas) and deeply nested counter-criticisms, the result is a tree structure. For example, as a discussion progresses, one of its trees might look like this:

Comments that aren’t criticisms – eg follow-up questions or otherwise neutral comments – are considered ancillary ideas. Unlike criticisms, ancillary ideas do not invert their respective parents’ statuses. They are neutral.

The idea of comment or question nodes is in my Discussion Trees essay: "A node can be e.g. a statement, claim, argument, explanation, question or comment."

The idea that the comments are neutral, rather than refuting their parent, is also in my essay: "Positive arguments, inconclusive negative arguments and explanatory comments are never decisive arguments." and "Decisive arguments shouldn’t be ignored. They’re mandatory to address. Other nodes don’t necessarily have to be dealt with."

The idea that criticisms refute their parent node is also in my essay: "Decisive (also called conclusive or essential) arguments argue that the parent is incorrect." and "If a decisive argument node or group is resolved as correct, then its parent must be resolved as incorrect."

My essay emphasizes distinguishing between neutral and non-neutral nodes: "Figuring out which arguments are decisive or not, and focusing on making and resolving decisive arguments, is the most effective way to reach a conclusion." I emphasize this distinction so much that I suggest deleting all indecisive nodes as an option: "You can convert a discussion tree to a strict debate tree by deleting all indecisive parts. More informally, you can include indecisive arguments and commentary in a debate tree as long as the decisive and indecisive parts are clearly labelled".

Again, criticisms are also just ideas, so the same is true for criticisms.

This is in my essay Artificial General Intelligence Speculations. I also told it to Hackethal on a call. I'll provide a quote from the call in the "Teaching Calls" section below.

Veritula implements a recursive epistemology. For a criticism to be pending, it can’t have any pending criticisms itself, and so on, in a deeply nested fashion.

That's how CF says criticism works. I described that system in my Discussion Trees essay. I've also talked about recursion in epistemology repeatedly, e.g. in Resolving Conflicting Ideas. I also talked with Hackethal about recursion on a call when he paid me to teach him about philosophy.

[Veritula] does not tell you what to think – it teaches you how to think.

Introduction to Critical Fallibilism: "Overall, CF helps explain how reasoning works. It provides tools and methods you can use to think better. It’s more about how to think than what to think. It enables you to think better rather than telling you what beliefs to have." While this isn't an original idea, it adds to the pattern where Hackethal keeps saying the same things as me.

Visions of Grandeur

Tom Nassis, who presumably didn't know Veritula misattributes CF's ideas to Popper, said: "Veritula deserves to scale to the size of Wikipedia." Hackethal replied (mirror):

I agree that Veritula deserves to scale to something huge.

Hackethal believes the CF ideas he's using, without crediting me, are extremely good, important and valuable. He's a fan of CF who has been trying to persuade people that CF is right while David Deutsch and Popper are wrong. But he calls it Popper being right and Deutsch wrong, and he pretends that CF doesn't exist. Actually, Popper's ideas were different than CF.

Quoting Benjamin Davies, Hackethal wrote (mirror):

I would also consider financially supporting someone who gave me good reason to think they had the vision, the motivation, and the technical skill to create it.

I’m interested. Let’s continue this discussion privately for now. Email me:

Hackethal is using my ideas to pretend to have a vision. He's trying to secure financial support for himself using my vision and my ability to develop good new philosophical ideas.

On his blog, Hackethal wrote:

somebody [in person at a Popperian event] suggested I start a movement called ‘Hackethalism’. I rather like that name

Some people apparently now believe he has great, original philosophical ideas. Which ideas are "Hackethalism"? If they're my ideas, we have a problem. If they're other ideas, which ones and where are they published? I've never seen Hackethal write significant, original ideas.

I fear that he wants to get rich and famous by taking my ideas and naming them after himself. It's flattering if he likes my ideas so much that he wants to put his name on them, but that's not OK. Renaming Critical Fallibilism to "Hackethalism" would go beyond normal plagiarism.

Naming it "Hackethalism" also contradicts his other strategy of attributing the ideas to Popper (which I refuted). Logically, CF's ideas can't, at the same time, be Popper's ideas that he wrote decades ago and also be new ideas called "Hackethalism".

Other Copying

Hackethal made an anti-misquotes website. Opposing misquotes was an ongoing campaign of mine for many years before Hackethal started writing similarly about it. When participating in my community, Hackethal was exposed to my ideas about quotations in multiple emails and chats before he started studying my work from a distance. On 2019-02-11, as a forum moderator, I brought up an issue with Hackethal's quoting to him because, like most newer members, he violated the group policies.

Hackethal also copies me in small ways, e.g. coloring italics red. For many years I've changed the color of italics in my articles so they visually stand out more. This can't be plagiarism since Hackethal doesn't claim credit for inventing the idea. I don't think colored italics are my original idea, but I think Hackethal probably copied the idea from me.

Hackethal probably also copied the way I write a lot in my own blog comments section following up on my own posts. It's an unusual thing to do. Copying it isn't plagiarism since Hackethal doesn't take credit for the idea. And I'm not claiming it's my original idea. But I do think he got it from me. It adds to the pattern of him studying and copying me.

Hackethal wrote on Veritula, "We can criticize theories for being arbitrary (which is another word for ‘easy to vary’)." Before The Beginning of Infinity was published, I argued to David Deutsch that "easy to vary" was the same issue as being arbitrary. I've made this point publicly too.

In Hackethal's Where's David Deutsch's Accountability? (mirror), we find more evidence that he's studied my writing. It seems inspired by me. It uses a lot of my approach to criticism and my style. It's his best post that I've seen. It has some good criticism of Deutsch. It isn't plagiarism and giving credit for general inspiration isn't mandatory (though it's often good, to and people often do it). While the post uses some of my methods, it doesn't explain those methods or otherwise try to take credit for inventing them. The substantive points critiquing Deutsch are adequately original to avoid plagiarism even though they're similar to points I've made. The use of Atlas Shrugged quotes is similar to my writing – I've used similar quotes from the same book for similar purposes before – but it doesn't cross a line by itself. It adds to the overall pattern and helps show how much Hackethal has learned from me. I've had multiple people comment about how some of his writing sounds extremely similar to mine (for both style and content).

I also have two examples from the comment section on that post, both written by Hackethal:

why hasn’t he [Deutsch] made any meaningful progress in the past ~15 years, possibly 25?

The 15 year end of the range comes from a simple analysis: Deutsch's book The Beginning of Infinity (BoI) involved progress but he hasn't done anything major since then. While I've said this, someone else could realistically come up with the same idea themselves.

But what's going on with the 25 year end of the range? That's saying Deutsch stopped making progress long before publishing BoI. How would Hackethal know that? It's an unusual thing to claim without insider knowledge. I knew Deutsch personally during that time period and helped with BoI (Hackethal did not). I've publicly commented about Deutsch knowing most of the ideas in BoI long before publication and not being very productive in the decade before publication. Am I Hackethal's source for this? I don't know of another public source for this claim besides me.

And think of how much more progress Deutsch could make if he was more methodical and did fewer, easier things!

This isn't plagiarism. It doesn't take credit for my ideas. It doesn't even explain the idea it's talking about. Someone else saying it might mean something different. But I interpret it as Hackethal talking about one of my ideas that I've discussed many times, but without citing me. I think it shows how immersed in my work he is that he writes short, vague references to my ideas, without giving links, and he seems to expect people to understand what he's saying.

Hackethal spent months in my community, hired me to teach him, and wrote around 50,000 words about me (including many quotes of obscure stuff I said, not just in essays but even in old chatroom archives). He's known about my work for seven years and seems to have studied it extensively. I don't think writing him about the same ideas as me, including my original ideas, is a coincidence.

Teaching Calls

In 2018 and 2019, Hackethal hired me to help him learn philosophy. He did not hire me to ghost write for him. I've never sold ghost writing services. He didn't ask for, nor receive, permission to use any of my ideas without crediting me.

During our 2019-01-27 call, we discussed Critical Fallibilism (specifically some of the core ideas that I also call "Yes or No Philosophy"). "David" refers to David Deutsch. This is edited slightly to delete some "umm", "like", ungrammatical repetition, and minor interjections like "yeah". Quotes:

Hackethal knows, and said on a call with me, that evaluating ideas in a binary way is my solution.

Hackethal knows that I developed new ideas like Yes or No Philosophy to address shortcomings in Popper's and Deutsch's philosophies.

During our 2018-12-24 call, I told Hackethal that criticisms are just ideas:

Confidential Documents

As part of the paid teaching, I sent Hackethal a 59 page CONFIDENTIAL DRAFT Critical Fallibilism Website.pdf. Perhaps I was too naive and trusting, although I already had already published other writing about most of the ideas in the document. I challenged critical preferences in 2010, then wrote other essays, then released my Yes or No Philosophy product in 2017. I taught my Critical Fallibilism course in 2020 and launched the Critical Fallibilism website in 2021. Hackethal launched Veritula in 2024.

Here are quotes from CONFIDENTIAL DRAFT Critical Fallibilism Website.pdf (I fixed the link because the website moved):

I also sent Hackethal Call 2 Notes.pdf (6 pages) which included this (I fixed the link):

Resources

Read and watch these to learn more about plagiarism:

Articles:

• Plagiarism Struggles (by social sciences professor Brian Martin)
• Brian Martin's publications on plagiarism and scientific fraud
• Avoiding plagiarism, self-plagiarism, and other questionable writing practices: A guide to ethical writing (by psychology professor Miguel Roig)
• Plagiarism in Publications: All about Being Fair! (by medical professor Neeraj Lalwani)

Videos:

• Plagiarism and You(Tube)  (4 hours about online creator plagiarism)
• What is Plagiarism and How Do I Avoid it? (8 minute introduction)
• What Is Plagiarism? (3 minute introduction)
• Avoiding Plagiarism: Writing With Integrity (35 minutes aimed at university students)
• Plagiarism Examples from Former Students (25 minutes)

Conclusion

Hackethal uses Critical Fallibilism ideas extensively without crediting me, particularly for Veritula. This is similar to how I previously accused his book of plagiarizing me.

Falsely saying CF ideas come from Popper (with no evidence, quotes or citations) does harm. Like plagiarism, it uses my ideas without crediting me. It also implies I plagiarized Popper. It confuses people about what Popper's views were and attributes unpopular ideas to him. It implies that Popper experts like David Deutsch and David Miller misunderstood Popper (Hackethal is implying that their books are bad.) It's worse than plagiarism.

If Hackethal changed his mind about what he said during our call ("so evaluating ideas in a binary way, that's your solution", "So Yes or No Philosophy is your philosophy that addresses shortcomings in both Popper's and Deutsch's philosophies?"), he should have explained that and argued his case using Popper citations. Attributing those ideas to Popper without evidence is unfair to me, Popper, and other Popperians.

It took me over twenty years to develop CF to what it is today. Hackethal is misappropriating my life's work as a shortcut. Instead of developing original ideas, which is hard, he found someone who isn't famous (me) and is using their ideas without crediting them.