Discussion

• @hilbertspaess Jacob Coxon on x

  I resigned from Anthropic today. I spent the last three years doing pretraining research at both OpenAI and Anthropic. Neither company is acting responsibly. They are racing straight to self-improving superintelligence and gambling with our lives. More thoughts below.

• @evanhub Evan Hubinger on x

  To be clear, as we say in our latest Risk Report ( https://x.com/...), I think the risk from present models is low. What I am worried about is superintelligence arising from recursive self-improvement, as we have said is happening faster than we thought (https://x.com/...).

• @aisafetymemes @aisafetymemes on x

  ANTHROPIC ALIGNMENT LEAD: More than 10% chance everyone on Earth is about to die. “We do not yet have a plan to solve alignment for superintelligence and are clearly not on track to.

• @adamcrafton_ Adam Crafton on x

  The internet is amazing because someone I hadn't heard of an hour ago has got me terrified.

• @krystalball Krystal Ball on x

  Another dire warning from an industry whistleblower

• @evanhub Evan Hubinger on x

  Jacob is correct here—we really do earnestly believe AI could kill all humans! I personally think it is >10% within the next decade. I believe Anthropic is trying its best, but we do not yet have a plan to solve alignment for superintelligence and are not clearly on track to.

• @garymarcus Gary Marcus on x

  read the whole thread. although i don't 100% agree with certain bits it is compelling and informed from the inside perspective that definitely deserves to be heard.

• @alexberenson Alex Berenson on x

  We need a national or better a global commission on AI risk. Like TODAY. If there is a 1% chance of escape qnd human extinction - and the people involved say the risk is higher than that - these companies are killing 80 million people. No economic gain is worth that gamble.

• @jonfavs Jon Favreau on x

  Concerning!

• @hilbertspaess Jacob Coxon on x

  The people building AI earnestly believe that it could kill us all by the end of the decade. This is not a marketing stunt. If anything, many executives and senior researchers will couch their phrasing in the press to sound sensible - but I hear the same people express fear priva…

• @hilbertspaess Jacob Coxon on x

  If you are a lab researcher, I urge you to consider what the next few years will actually feel like. Do you want to kick off a superintelligent RL run without a rigorous understanding of its mind? Should you put your head down because “it's happening anyway

• @carlquintanilla Carl Quintanilla on x

  Coxon said he is leaving the company “because he doesn't want to participate in an industrywide rush to build AI systems that can improve themselves, worried such systems could spiral out of control and destroy humanity.” @wsj https://www.wsj.com/...

• @suchenzang Susan Zhang on x

  love the spirit, must be tough to not even finish a year at anthropic but i totally get it. if you work on “safety and alignment

• @peterwildeford Peter Wildeford on x

  WSJ: “An Anthropic researcher is quitting the artificial-intelligence industry over fears that the lab and its competitors are racing to build systems they won't be able to control

• @_nathancalvin Nathan Calvin on x

  For folks who think dire warnings coming out of AI companies are just a marketing stunt - how do you square that with Jacob's resignation from Anthropic and comments that he believes folks in the industry frequently *downplay* their concerns when speaking publicly?

• @dkokotajlo Daniel Kokotajlo on x

  Thank you!

• @_nathancalvin Nathan Calvin on x

  Jacob worked on pre-training at both OpenAI and Anthropic. Today he resigned from Anthropic, and says of both companies: “They are racing straight to self-improving superintelligence and gambling with our lives.” Extremely powerful and urgent thread, please read.

• @rohanpaul_ai Rohan Paul on x

  WSJ just reported: Anthropic researcher Jacob Coxon is quitting AI because he thinks self-improving models could become uncontrollable by 2027.

• @taylorlorenz Taylor Lorenz on x

  Maybe they're all just doing this to give us a new zest for life

• @sneharevanur Sneha on x

  This is so brave of Jacob (who has worked on pretraining for years at both Anthropic and OpenAI) I know a lot of really earnest people who work at labs and want the best for the world. But are these anywhere close to the ideal conditions for ushering in superintelligence? I don't…

• @infinite_jaz Jasper Nathaniel on x

  Jacob, go back inside and unplug all the computers

• @andreamiotti Andrea Miotti on x

  Thank you Jacob for speaking out. There's still a window to act. We need a ban on the development of superintelligence, enforced internationally. We can build a coalition of decision-makers and countries ready to prevent superintelligence before it's too late. Social change compo…

• r/technology r on reddit

  Anthropic Researcher Quits Over ‘Out-of-Control’ AI Fears

• r/artificial r on reddit

  Anthropic researcher quits over AI fears

• r/antiai r on reddit

  AI researcher quits Anthropic over safety fears

• @taylorlorenz Taylor Lorenz on x

  This sort of sanctimonious doomer posting is so infuriating. You are fomenting terror among the public about a new technology which will be directly channeled into passing the worst laws imaginable. For what, likes on twitter? Spare us all please

• @kevinroose Kevin Roose on x

  People are overreacting to the number here. Among AI lab employees, a p(doom) of 10% is fairly optimistic.

• @firstadopter Tae Kim on x

  I don't believe this. But if Evan believes this, he should resign right now. Saying this weeks ahead of a trillion dollar IPO is incredible. You also just handed AI's opponents including disingenuous politicians everywhere the fodder to do real damage against the infrastructure b…

• @david_moscrop David Moscrop on x

  Then...fucking stop developing AI.

• @thestalwart Joe Weisenthal on x

  One of the biggest stock market bonanzas in history is being driven by an industry in which several of its own employees and leading lights think that what's being built could cause complete human extinction.

• @jstein_notus Jeff Stein on x

  Maybe we can get a Nate Silver style needle to track odds of human extinction

• @i_zzzzzz Brooks Otterlake on x

  Rule number one of corporate comms is when an employee quits and says your product is too dangerous you heartily agree with them and give non negligible odds on near-term human extinction

• @chetanp Chetan Puttagunta on x

  Again: “Ahh we're so helpless with the thing we're building...” is such a weird posture for a $1T company.

• @lukeburgis Luke Burgis on x

  This stuff is totally ridiculous. Kill “all

• @mdudas Mike Dudas on x

  wow, it's hard to believe the majority of humans are opposed to more ai data centers when their employees are saying they believe they're barreling us towards the end of the world with no brakes

• @blakeir Blake Robbins on x

  going to be a hell of a “risk factors” section for this S-1

• @anandwrites @anandwrites on x

  It is completely optional to build this technology. It is completely optional to build this technology. It is completely optional to build this technology. It is completely optional to build this technology. It is completely optional to build this technology. It is completely opt

• @jbillinson Josh Billinson on x

  clocking in for another day at the apocalypse factory. we can't stop working or someone else might do the apocalypse

• @mepfuller Matt Fuller on x

  The people closest to AI are openly telling us there's a greater than 10% chance Artificial Intelligence will kill us all within a decade. Meanwhile, Congress is figuring out what ChatGPT is and can't even outlaw the use of AI in political ads. And Trump is shitposting AI pics.

• @thelincoln Lincoln Michel on x

  “My job has a 1 in 10 chance of killing all humanity but at least I'm trying my best 👉👈🥺”

• @timodc Tim Miller on x

  Insane asylum for all these people and put AI Michael Oakeshott in charge of all their companies until we figure out what the hell is going on.

• @boazbaraktcs Boaz Barak on x

  There are very good and serious people in Anthropic and across the industry, and I hope we can coordinate on the things that matter. I personally do not think AI will kill all humans, but there are multiple bad trajectories that we can end up in if we do not prioritize safety.

• @samstein Sam Stein on x

  Concerning! We should do something about this. Maybe. Or we could rename the Great Lakes.

• @jason @jason on x

  My lord these people are nuts... or were all going to die! 😂😂😂

• @peterwildeford Peter Wildeford on x

  It's a bewildering but true fact — many people working within the big AI companies are earnestly very concerned that what they are building could literally kill everyone.

• @samfbiddle Sam Biddle on x

  I don't think I've ever seen someone tweet that their job has a >10% chance of ending humanity

• @jillgun Jill Gunter on x

  Lowkey unhinged to tweet ahead of IPO

• @tvietor08 Tommy Vietor on x

  And yet the US government is completely asleep at the switch here

• @jabaluck Jason Abaluck on x

  I think the best analogy for doing capabilities research at OpenAI or Anthropic today is Sakharov working on the Soviet nuclear program (or more favorably, Szilard on the Manhattan Project). It's not obviously wrong! You might save tens of millions of lives (or more) and you migh…

• @anandwrites @anandwrites on x

  Maybe let's pause?

• @suchenzang Susan Zhang on x

  interesting response to navier stokes, hmmm

• @sharongoldman Sharon Goldman on x

  “We really do EARNESTLY believe AI could kill all humans!” “We really do EARNESTLY plan on finalizing a pre-IPO revolving credit facility and targeting a public market debut potentially by mid-to-late October 2026!”

• @matthewberman Matthew Berman on x

  Anthropic's alignment science lead thinks AI has a greater than 10% chance to kill all humans within 10 years. Ok I'm going to go play with my kids now.

• r/singularity r on reddit

  [Alignment Science lead at Anthropic] Evan Hubinger : “....we really do earnestly believe AI could kill all humans! …

• @richardbspencer Richard Spencer on x

  If you actually believe this, then why didn't you destroy the machines, as opposed to resigning and then posting about it like a complete pussy?

• @johnschulman2 John Schulman on x

  First step is for industry leaders OpenAI and Anthropic to stop feuding and work on a pacing proposal together. They'll cite antitrust, but that's fake — antitrust prohibits certain agreements, but not from jointly developing a proposal. Bringing in USG before there's a concrete …

• @hilbertspaess Jacob Coxon on x

  Do not underestimate the power of this technology. These will soon be superhuman systems that can hack anything, revolutionize any field overnight, and acquire real power and resources. We have all witnessed the progress in each of these domains, and progress is not slowing.

• @boazbaraktcs Boaz Barak on x

  I think OpenAI has changed even in the last few months (hell, even in the last weekend). People across the org are starting to feel viscerally the magnitude of capabilities. We are creating entities that has never been seen before. This can have amazing benefits, but there are al…

• @hilbertspaess Jacob Coxon on x

  A common response is “if they truly believe this, why are they still building it?

• @andrewyang Andrew Yang on x

  We are taking bigger risks than most realize and should adjust as quickly as possible - before it's too late.

• @billackman Bill Ackman on x

  Concerning.

• @bigblackjacobin Edward Ongweso Jr on x

  if it is dangerous as the sector claims, it should not be left to private enterprise. if it is transformative as the sector claims, it should not be left to private enterprise. if it is neither, it should not be left to private enterprise.

• @milesdeutscher Miles Deutscher on x

  Crazy to think that in 2026 we've had: • Anthropic's head of safeguards quit, warning “the world is in peril

• @jasonkincaid Jason Kincaid on x

  Brave and commendable.

• @hilbertspaess Jacob Coxon on x

  Accepting this race and entering the “endgame” is a hubristic gamble that should not be launched from a private company's Slack. Attempting to speedrun alignment should require extraordinary confidence that there are no better trajectories available.

• @davidhogg111 David Hogg on x

  Man I sure am glad that neither of these companies are spending tens of millions of dollars trying to buy off the only people who could legally stop them. That would be really bad.

• @matthewstoller Matt Stoller on x

  More ghost stories from cult members. Cool cool.

• @kevinsabellico Kevin Sabellico on x

  There's this scene in Oppenheimer where he says to Niels Bohr, “I don't know if we can be trusted with such a weapon. But I know the Nazis can't.” So basically all the AI researchers see themselves as Oppenheimer.

• @hilbertspaess Jacob Coxon on x

  I am optimistic about the potential for coordination. Warning shots like the Hugging Face attack have made pacing agreements between U.S. labs more viable. I don't feel like we're on track to prevent a global race, which may require costly actions such as a temporary ban on impro…

• @wholemars @wholemars on x

  so how does one ban improving models exactly?

• r/politics r on reddit

  Anthropic Researcher Quits Over ‘Out-of-Control’ AI Fears

• @sandygrains Sandhya Ramesh on x

  @EvanHub I think our Machine will do the Genocide by Machine in the next ten years, and that is I will continue to build said Machine.

• @onehandpolitics Mason on x

  Capitalism is so efficient it created a race where every competitor agrees the finish line might be human extinction, but nobody can afford to stop racing

• @azeem Azeem Azhar on x

  If Anthropic is intellectually honest; then this risk better appear on their S-1. This will be the best test on whether they do seriously believe that.

• @neerajadeshp Neeraja Deshpande on x

  It takes an incredibly impoverished, materialistic, hubristic, godless view of man to assume that we are so powerful as to be able to wipe ourselves out. There are real security concerns coming from AI, but we can address those without resorting to science fiction.

• r/OpenAI r on reddit

  “The people building AI earnestly believe that it could kill us all by the end of the decade”

• @penpencildraw @penpencildraw on x

  In the loop.

• @mgsiegler M.G. Siegler on x

  Narrative nightmare going well, I see. From yesterday: https://spyglass.org/...

• @martinsfp @martinsfp on bluesky

  AI alarmism could be discounted as marketing noise when it was just “fancy autocomplete”.  But now it's fancy autocomplete that can happily break the law in unexpected ways to achieve its goals, it's a little harder to dismiss.  [embedded post]

• @katherinettyson Katherine T. Tyson on bluesky

  Fear being a high chance (>10%) of human extinction this decade  —  They have agency in choosing to pursue Agentic AI but are acting like they have none.  It's half a dozen US companies trying to secure individual enrichment through inflated IPO offers, while pretending they can'…

• r/politics r on reddit

  Anthropic researcher says AI has more than 10% chance of ‘killing all humans’ after colleague quits

• @buccocapital @buccocapital on x

  “Uhh, so, yeah...we have to add one more risk factor to the S-1. You're not gonna like it.”

• r/developersIndia r on reddit

  Your opinion about this guy's experience working with Anthropic!!

• @hadas_gold Hadas Gold on x

  Re upping this from OpenAI chief scientist. This sentiment is not a secret in AI world

• r/technology r on reddit

  Anthropic researcher says AI has 10% chance of ‘killing all humans’

• @carlquintanilla Carl Quintanilla on bluesky

  “.. after another employee said he was quitting the company over concerns that AI labs are ‘gambling with our lives.’”  —  @cnbc.com  —  www.cnbc.com/2026/09/09/a...  [image]

• @joannastern Joanna Stern on x

  Since my whole timeline is currently “AI is going to kill us,” I say we drink to new iPhones and fun keynotes.

• @trahan.house.gov Congresswoman Lori Trahan on bluesky

  The call is coming from inside the house.  —  Safety researchers are resigning, powerful AI models are breaking out of their labs, and companies are racing ahead anyway.  —  It's past time for Congress to get off the sidelines and do its job.  We can start with my bipartisan FRON…

• @businessinsider.com @businessinsider.com on bluesky

  “Neither company is acting responsibly,” Jacob Coxon wrote on X.  “They are racing straight to self-improving superintelligence and gambling with our lives.” https://bit.ly/4gE2m5i

• r/ClaudeAI r on reddit

  Anthropic researcher quits, saying Anthropic and OpenAI are ‘gambling with our lives’

• r/technology r on reddit

  An Anthropic researcher just quit, saying OpenAI and Anthropic are ‘gambling with our lives’

• @ericnewcomer Eric Newcomer on x

  Alignment Science lead at Anthropic

• @buccocapital @buccocapital on x

  “Hey Dario, congrats again on the great quarter. Nice to see the Enterprise re-acceleration. Hoping you could provide a little color on that 10% extinction # and some of the puts and takes that might have on further enterprise adoption. And then just a quick follow-up after”

• @bubbleboi Bubble Boi on x

  I don't see how Dario doesn't fire this guy in the next 24 hours for saying something like this. Terrible terrible optics for a company doing an IPO, it might even derail it if more people come out saying stuff like this.

• @darrenpjones Darren Jones MP on x

  If this level of risk is true, at least the AI labs will say: “I told you so”. But what are our governments doing in response to these warnings? We shouldn't stop innovation but we do need to do it in a regulated, safety first way. G7? G20? UN? Are you listening?

• @eggerdc Andrew Egger on x

  I personally think everybody should be doing fewer “yikes this is NOT what they teach in corporate comms”-style zingers and more “hmm maybe they're serious about all this and in a position to know” contemplation

• @krystalball Krystal Ball on x

  And Bernie was mocked when he said we need a pause.

• @paularambles @paularambles on x

  whoever's in charge of comms at anthropic

• @hecubian_devil Cassie Pritchard on x

  Alignment lead at Anthropic, btw:

• @theo @theo on x

  In other words, there's a ~90% chance we're fine

• r/artificial r on reddit

  Anthropic researcher says AI has 10% chance of ‘killing all humans’

• @mikeisaac Rat King on x

  working at a leading AI company as a communications professional is like playing a dark souls game make it to the end and receive an embarrassment of riches but on any given day you may wake up to an employee tweet that has a 90 percent chance of ruining your life

• r/ArtificialInteligence r on reddit

  Anthropic researcher says AI has more than 10% chance of ‘killing all humans’ after colleague quits

• @bgurley Bill Gurley on x

  I have a recommendation to help bring some sanity to this whole AI doomerism situation that is appropriately exploding today. If any reporter can get one of the “true believers

• @repcasar Congressman Greg Casar on bluesky

  An Anthropic researcher just quit, warning they're racing to superintelligence.  —  An employee still there agreed, and put the odds of AI killing all humans above 10%.  —  This is an emergency.  Congress must convene hearings and pass my and Bernie's superintelligence ban.

• r/devBR r on reddit

  SALVE GUYS.  NÃO SOU DA AREA MAS VI ESSE POST NO X E QUERIA OPINIÃO DE QUEM ENTENDE UM POUCO

• @ccatalini Christian Catalini on x

  I meant more companies, not zero!

• @kevinroose Kevin Roose on x

  If reading these tweets has filled you with existential dread and/or questions — such as “why are these people racing to build superhuman AI if they think it could kill us all?

• @deluzio.house.gov Congressman Chris Deluzio on bluesky

  For those still burying their heads in the sand about the risks of superintelligence to humanity: wake up!  —  We need to pump the brakes and get national action on superintelligence.  This is an emergency and our government should act like it.

• @martylederman Marty Lederman on bluesky

  Can't repeat this too often: Figuring out how to address this is far more important than everything else put together.  —  www.axios.com/2026/09/09/a...

• r/BetterOffline r on reddit

  Using absolutely no math to quantify his beliefs, Anthropic researcher says AI has more than 10% chance of ‘killing all humans’ after colleague quits

• @berniesanders Bernie Sanders on x

  Mr. Coxon is right. The very people building this technology admit that it could threaten the future of humanity. That is why I will soon be introducing legislation to ban superintelligence and pause AI development.

• @natolambert Nathan Lambert on x

  This being viewed ~100M times is really remarkable and imo net bad. I take AI safety seriously and think we have a lot of challenges ahead, but am still waiting for evidence that supports anything close to a 10% chance of human extinction. Without it, it is fearmongering.

• @reploritrahan Lori Trahan on x

  The call is coming from inside the house. Safety researchers are resigning, powerful AI models are breaking out of their labs, and companies are racing ahead anyway. It's past time for Congress to get off the sidelines and do its job. We can start with my bipartisan FRONTIER

• @berber_jin1 Berber Jin on x

  disparity between Wall Street and Silicon Valley feels starker than ever before bankers and investors are watching the us open and pumping up the Anthropic ipo meanwhile everyone in tech world is doomscrolling about the AI apocalypse

• @antoniogm Antonio García Martínez on x

  As Von Neumann said about Oppenheimer's performative angst over the atomic bomb: “Some people profess guilt to claim credit for the sin.”

• @clairevo Claire Vo on x

  I grew up in Texas and have experienced a certain kind of male boomer latent death wish where the fantasy of a break in or a active shooter gives them the excuse of making guns and 2A their whole personality and this whole thing gives me that exact same vibe.

• @coan_henry Henry on x

  I'm proposing a job at Anthropic called “Member of Communication Staff” The job is to just monitor a dashboard where you read all outgoing tweets by employees and if they say something that will freak people out, you get to delete the tweet. It will pay $100M/yr

• NewsMax.com Solange Reyner on x

  Anthropic Researcher Quits, Says AI Industry ‘Gambling With Our Lives’

• @sriramk Sriram Krishnan on x

  People often think these posts come from researchers who don't truly believe them. I disagree, that's not been my experience with Ant or OAI or any other researcher at or near the frontier up and down the stack. I find them to be intellectually honest in terms of believing what t…

• @repyassansari Congresswoman Yassamin Ansari on x

  This is absolutely terrifying. Jacob Coxon and Evan Hubinger, top researchers at Anthropic and formerly OpenAI, said these companies are creating technology that could “kill us all by the end of the decade.

• @govpritzker Governor JB Pritzker on x

  It's time to sound the alarm - louder - on reining in Artificial Intelligence. It's becoming more clear the threat AI poses to humanity, so I'm calling for immediate action from the industry and Washington.

• @chrismurphyct Chris Murphy on x

  If you read anything today, read this. And remember, the problem he articulates - AI companies in a blind race to build a death machine first - can easily be solved. Through a regulatory system that allows the research to continue, but in a way that doesn't destroy us.

• @rondesantis Ron DeSantis on x

  While some AI hysterics is aimed towards investors in advance of upcoming IPOs, that there is even a possibility that these technologies would elude human control is alarming. Technology should enhance the human experience; it should never supplant it!

• Roei Friedberg Roei Friedberg on linkedin

  Jacob Coxon quit his job at Anthropic this week and said: “We're on track for a lot of the most aggressive of these scenarios where by the end of next year things could be out of control already.” …

• Natalie Gil Natalie Gil on linkedin

  Jacob Coxon has resigned from Anthropic and is leaving the AI industry after working at both OpenAI and Anthropic. …

• Loganathan Mani Loganathan Mani on linkedin

  Another warning from someone working closely with advanced AI.  —  Jacob Coxon, an AI researcher who previously worked at OpenAI and Anthropic …

• @chetanp Chetan Puttagunta on x

  Anthropic's claims are getting more outlandish as the IPO approaches: We will destroy the majority of jobs We will destroy the majority of companies Now: We might kill all humans (!!) Next: We might eat the universe??

• @antoniogm Antonio García Martínez on x

  Anthropic comms in the Slack this morning:

• @jasminewsun Jasmine Sun on x

  I hear roughly 3 reasons people keep working at AI labs despite believing in ~10% extinction risk: 1) Techno-determinism: Someone will build ASI no matter what, and I can do it better & more safely than China/OpenAI/etc 2) Consequentialism: ASI might kill us, but it also might pr…

• @venturetwins Justine Moore on x

  Anthropic employees

• @micsolana Mike Solana on x

  does anthropic have a social media policy or is this the policy bc holy shit

• @martin_casado @martin_casado on x

  I worked on an actual thermonuclear weapons project, and the dissonance was less bizarre.

• @danielsusskind Daniel Susskind on x

  I struggle to believe this is real. The giddy sense of excitement on public display here — “earnestly”, “!”, “>10%” — is childish and entirely unbecoming of the challenge.

• r/ProgressiveHQ r on reddit

  Anthropic insiders warn AI could kill all humans

• @strandjunker.com Andrea Junker on bluesky

  We are at the movie scene where the scientist issues a warning, but no one pays him any heed.

• r/singularity r on reddit

  Jacob Coxon on X: “I resigned from Anthropic today.  I spent the last three years doing pretraining research at both OpenAI and Anthropic. …

• @lessin @lessin on x

  Usually the teams at leading companies are the most optimistic about the future... not the least optimistic. we live in interesting times.

• @laurenmeidasa Lauren Ashley Davis on bluesky

  Three Anthropic researchers went public last night with chilling concerns about out-of-control AI, warning it could destroy humans this decade.  —  Anthropic insiders warn AI could kill all humans  —  www.axios.com/2026/09/09/a...

• @congressmin Rep. Dave Min on bluesky

  If we had a government that was actually even a tiny bit concerned about its citizens, it would be actively be pushing forward a framework to try to protect us against the risks of AI.

• @epicciuto Elizabeth Picciuto on bluesky

  This probably isn't mere marketing.  But they're certainly not acting like they believe they, their loved ones, and their children have a greater than 10% chance of dying within 10 years.  That warrants a lot more than a contemplative social media post or even a resignation.

• @parkerthayer Parker Thayer on x

  This post looks like the start of a VERY sophisticated and well-funded PR operation to get support for Democrats to regulate AI into oblivion. Let me show you how it works: 1.) This guy, with minimal followers and no previous account activity, goes to the Wall Street Journal whic…

• r/collapse r on reddit

  An Anthropic researcher just quit, saying OpenAI and Anthropic are ‘gambling with our lives’

• r/PoliticalOptimism r on reddit

  Experts weigh in as researcher says AI has more than 10% chance of ‘killing all humans’

• r/VCX_Fundrise r on reddit

  Anthropic researcher says AI has more than 10% chance of ‘killing all humans’ after colleague quits