OG GenAI Skeptic; spoke at US Senate. Warned about hallucinations in 2001. Advocating world models & neurosymbolic AI ever since. Author, Marcus on AI & 6 books

Joined December 2010
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31 Aug 2025
Three thoughts on what really matters: 1. Fuck cancer 2. Friends are irreplaceable 3. The new "Marcus test" for AI is when AI makes a significant dent on cancer May that happen sooner, much sooner, rather than later. In memory of my childhood friend Paul.
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Did Trump just kill Generative AI? 🤔
Replying to @GaryMarcus
Taken at face value, the Trump admin. ban on Fable calls into question the entire AI industry. The underlying technology is non-deterministic and therefore inherently unpredictable. It’s impossible to build in safeguards to reliably prevent jailbreaks. This is a turning point.
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🇨🇳 vs 🇺🇸 China plays the long game; the U.S. is so ego-bound it couldn’t wait a weekend—and maybe did lasting harm to the credibility of the U.S. AI industry as a result.
Interesting article with new details on the lead up to the export controls. Both sides are telling very different stories. Anthropic says they were given a 90 minute hard deadline to pull both models. The administration says their concerns were not taken seriously.
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So funny how so many people are rediscovering so many things I pointed out in late 2022. (In this case in my essay “AI’s Jurassic Park Moment”)
AI's Core Flaw: "Mass Regurgitation Of Misinformation" zerohedge.com/ai/ais-core-fl…
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never was
This might be a come to Jesus moment if the regulators suddenly realize that jailbreak prevention isn't real.
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is that actually true that @karpathy was hired to “run recursive self improvement”?
Everyone can see Anthropic's hypocrisy in pushing toward RSI while warning that doing so creates catastrophic risk. These All-In guys might not know the insiders' party line, the galaxy-brained “someone else will build it if we don't” logic. But they're still right: It's crazy.
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Gary Marcus retweeted
Instead of discussing how Elon Musk is now the world's first trillionaire, we should talk about how he killed hundreds of thousands of people through his dismantling of food and medical aid to poor countries currentaffairs.org/news/how-…
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Really proves how little Sacks knows about AI… “Just fix the jailbreak man”
DAVID SACKS SAYS ANTHROPIC'S EXPORT CONTROL WAS DUE TO COMPANY NOT WANTING TO FIX JAILBREAK ADMIN HOPES THEY REMEDIATE SAFETY ISSUE TO LIFT EXPORT CONTROL: X
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victory to whichever company has the better model, er, um, White House access!
Replying to @GaryMarcus
To me this signals a dangerous precedent that AI companies can use the government against each other for advantage.
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Gary Marcus retweeted
Replying to @GaryMarcus
Is this now the stage where we have an adult conversation about neurosymbolic AI? And can we accept that LLMs have some things they're great at, but they are only one tool in a bigger toolbox? God I hope so.
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Capitalism with a giant government thumb on the scale ain’t gonna work.
Three months ago, @DeptofWar kicked @AnthropicAI out of our building—forever. Every passing day proves why that was the right move. 🇺🇸
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Gary Marcus retweeted
Amazon invested $50 billion in OpenAI earlier this year
Breaking: Amazon CEO Andy Jassy was among the tech leaders who raised concerns to senior Trump officials this week re: security risks in Anthropic's newest models. Those convos set in motion the government's new export controls on foreign national access to Mythos and Fable.
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as far as i know, that’s the main one
Replying to @GaryMarcus
So we’re down to “coding assistant for *seasoned programmers*” as the only good, scalable use case for LLMs… right?
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Crazy to see previously antiregulatory people suddenly fine with government shutdown of a company’s showcase product with zero public transparency. Absent bipartisan and independent scientific oversight, the approach outlined below leaves (a) the government with too much room to be arbitrary and (b) business with too much reasons to worry about what might come next.
I’ve had a number of conversations with folks inside and outside government about the current situation with Anthropic, and here is what I believe to be true: — As we know, Anthropic publicly released its Mythos class models earlier this week under the commercial name Fable. — Fable is Mythos with guardrails. But if those guardrails fail, then you’ve exposed Mythos and its advanced cyber capabilities to people who shouldn’t have them. (Keep in mind that Anthropic itself widely promoted the idea that Mythos was a cyberweapon and needed to be regulated as such. They asked for government regulation of Mythos and championed the guardrails on Fable. If there is a vulnerability — big or small — it is Anthropic’s responsibility to patch.) — A highly credible trusted partner of both Anthropic and the USG who was testing Fable came forward with a jailbreak of those guardrails. The Admin asked Dario to fix the jailbreak or de-deploy the model. Dario refused. — In their blog post, Anthropic defended its decision by saying the jailbreak isn’t serious. That is not what the trusted partner and the USG believe; nor is that kind of minimizing language consistent with Anthropic’s brand as the AI safety company. It’s difficult to fathom how they could claim a jailbreak allowing operability of a cyber weapon could be defined as not “serious.” — In the past, Anthropic has always said that safety must be top priority and taken super seriously. In this case, Anthropic prioritized the continued offering of the consumer model over safety. — In reaction, the Admin issued the export control. The Admin did this reluctantly. It’s been very surprised that Anthropic hasn’t wanted to cooperate with a reasonable safety request (ie fixing the jailbreak issue). Anthropic’s reaction is very much at odds with their branding and ethos as a safe AI research community. — The Admin’s hope now is that Anthropic remediates the safety issue, the export control is lifted, and Fable goes back into general release. The Admin wants all of this to happen as soon as possible. It is frankly bewildered that Anthropic hasn’t wanted to comply with safety requests that it previously said were its highest priority. — Those trying to misdirect and tie this action to the prior DoW/Anthropic issues are wrong. The Admin values Anthropic’s technical capabilities and feels that this issue, while serious, should be easily resolved. The ball is in Anthropic’s court.
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The Alexandr Wang era is working out great. About as well as the Metaverse did.
This headline is pretty accurate based on Meta folks I’ve been talking with Meta is successfully destroying their formerly standout engineering culture: forcefully assigning standout devs to this unit the layoffs It makes no rational sense. Hiring from Meta never been easier!
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Vibe Coding, 2025-2026 RIP 🪦 Turns out you do still need skilled software engineers in the loop, just like many of us said all along.
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putting aside all political differences, some administrations I could name just aren’t *good* at governing.
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