Yann LeCun Leaves Meta: 'LLMs Are a Dead End'

The Most Influential AI Scientist Says Goodbye to Zuckerberg

My verdict is clear: what just happened at Meta is an earthquake for the entire artificial intelligence industry. Yann LeCun, the man who invented convolutional neural networks, winner of the Turing Award (the Nobel Prize of computing), and one of the three "Godfathers of AI" alongside Geoffrey Hinton and Yoshua Bengio, has left Meta after 12 years.

But he didn't leave quietly. LeCun departed with a message that has shaken Silicon Valley: "LLMs are basically a dead end when it comes to superintelligence."

Translation: ChatGPT, Claude, Gemini, and all the language models that dominate today's AI conversation... according to one of the most respected scientists in the field, they're the wrong path.

I won't sugarcoat it: when a 65-year-old man with a Turing Award and decades of fundamental contributions to AI says the trendy technology is a dead end, you need to listen.

The Last Straw: Reporting to a 28-Year-Old CEO

To understand why LeCun left, you need to understand what happened in June 2025. Meta invested $14 billion in Scale AI for a 49% stake. As part of the deal, Scale AI founder Alexandr Wang left his company to join Meta as its first Chief AI Officer.

Wang is 28 years old. LeCun is 65. The age difference is 37 years.

After the deal, Wang took over Meta Superintelligence Labs (MSL), Meta's new AI division. This technically placed LeCun under Wang's supervision.

LeCun's reaction was public and unfiltered:

"You don't tell a researcher what to do. And you certainly don't tell a researcher like me what to do."

On Wang specifically:

"Alex is young and inexperienced. He has no experience with research or how you practice research. He's intelligent and learns quickly, but doesn't yet grasp what attracts — or alienates — top researchers."

Who is Alexandr Wang?

Wang built Scale AI, a data labeling company for training AI models. Valued at $29 billion after Meta's investment. But according to LeCun, labeling data isn't the same as understanding the fundamental science of artificial intelligence.

"LLMs Are a Dead End": LeCun's Argument

This is where the story gets really interesting. LeCun didn't just leave Meta — he's betting his entire reputation and legacy on a radically different vision of AI's future.

His exact words:

"I'm sure there's a lot of people at Meta, including perhaps Alex, who would like me to not tell the world that LLMs are basically a dead end when it comes to superintelligence. But I'm not gonna change my mind because some dude thinks I'm wrong. I'm not wrong. My integrity as a scientist cannot allow me to do this."

Why Does He Say LLMs Are a Dead End?

LeCun's argument boils down to this: LLMs (Large Language Models) like ChatGPT and Claude are "disembodied mimics" that are "auto-completing on a cosmic scale." They perform well with language, but they don't understand the world.

The Cat Analogy

LeCun uses a powerful analogy: a house cat with its walnut-sized brain has something the world's most advanced AI doesn't have — a world model.

The cat:

• Understands physics intuitively
• Calculates trajectory, friction, and velocity
• Comprehends object permanence
• Operates in a 3D world with genuine reasoning

ChatGPT can write an essay about physics, but it doesn't "understand" physics the way a cat understands that if it jumps wrong, it's going to fall.

"We don't need an AI that can recite encyclopedias; we need an AI that can understand the world with its eyes and hands."

AMI Labs: The $5 Billion Bet

LeCun didn't retire. He launched AMI Labs (Advanced Machine Intelligence Labs), a startup aiming to build what he calls "world models."

The Numbers

Who's Investing?

Potential investors reportedly include:

• Cathay Innovation
• Greycroft
• Hiro Capital (LeCun is an advisor)
• 20VC
• Bpifrance (French public investment bank)
• HV Capital

And here's the unexpected twist: Meta will be a partner of AMI Labs. Despite LeCun's public criticisms, Zuckerberg apparently wants to keep a foot in the "world models" game.

What Will They Build?

AMI Labs will be based on V-JEPA, an architecture LeCun created at Meta. These models:

• Train on video and spatial data (not just text)
• Can plan, reason, and maintain information over time
• Simulate cause-and-effect and predict outcomes
• Are designed to solve the structural hallucination problem

Meta's Internal Drama

LeCun's departure exposed deeper problems at Meta. According to him, Llama 4 benchmarks were "fudged a little bit":

"Teams used different models for different benchmarks to game the numbers. Mark was really upset and basically lost confidence in everyone who was involved. So he basically sidelined the entire GenAI organization."

Additionally, LeCun predicted a talent exodus:

"A lot of people have left, a lot of people who haven't yet left will leave."

The data backs this up:

• 600 employees laid off from Superintelligence Labs in October 2025
• Meta's model adoption among developers dropped from 19% to 11%
• The open-source community is migrating to alternatives like Alibaba's Qwen and Mistral

LeCun's Track Record: Why You Should Listen

If you ask me directly why I think LeCun deserves attention, here's the data:

Fundamental Contributions

1. Convolutional Neural Networks (CNNs) - 1980s

   • The foundation of all modern image recognition
   • First to train a CNN on handwritten digit images

2. LeNet - AT&T Bell Labs

   • Handwriting recognition system that read over 10% of all US checks in the late '90s

3. 2018 Turing Award

   • Shared with Geoffrey Hinton and Yoshua Bengio
   • For "conceptual and engineering breakthroughs that have made deep neural networks a critical component of computing"

His Prediction Track Record

• Neural networks: LeCun defended them when they were a joke in the field
• Deep learning: He promoted them when they were a fantasy
• Now: Betting his reputation that "world models" are the real AI revolution

LeCun is standing in the middle of the biggest gold rush built on LLMs and calmly, publicly, and repeatedly calling it another dead end.

Who's Right?

My verdict is clear: we have no way of knowing yet. But here are the arguments on each side:

Argument in LeCun's Favor

• LLMs keep hallucinating after years of development
• They can't genuinely reason about the physical world
• OpenAI is burning $115 billion through 2029 with no profitability in sight
• LeCun has been right before when the majority was wrong

Argument in LLMs' Favor

• ChatGPT and Claude are already generating billions in revenue
• "World models" are still largely theoretical
• The entire industry has bet trillions of dollars on this approach
• Incremental improvements could solve hallucination problems

What This Means for You

If You Work in AI

• Pay attention to "world models" as an emerging area
• Diversification of approaches may be prudent
• Talent is migrating — opportunities may arise

If You Invest in Tech

• AMI Labs' $5B valuation will be a market confidence indicator
• If LeCun is right, companies 100% focused on LLMs could face trouble
• Meta is keeping a foot in both camps (hedging signal)

If You Use AI as a Tool

• LLMs will remain useful regardless of the academic debate
• But don't expect ChatGPT to "understand" the world anytime soon
• Current limitations (hallucinations) will likely persist

Conclusion: The Prophet of the Dead End

Yann LeCun is 65 years old, has a Turing Award, and decades of contributions that founded the AI revolution. He just left the most prestigious job in the field to tell the world that the trendy technology — the one that has generated trillion-dollar valuations — is the wrong path.

He could be wrong. OpenAI, Anthropic, Google, and Microsoft have bet everything on it.

But he could also be right. And his track record suggests that when Yann LeCun goes against the current, it's worth listening.

In 3-5 years we'll know who was right. Meanwhile, LeCun will be in Paris building his vision of what AI really should be.

"Nobody in their right mind would use LLMs of the type that we have today" — within 3-5 years.

Time will tell if it's prophecy or hubris.

Frequently Asked Questions

Why did Yann LeCun leave Meta?

LeCun left Meta after the company invested $14 billion in Scale AI and put its 28-year-old founder, Alexandr Wang, as Chief AI Officer. LeCun considered Wang "young and inexperienced" in research and didn't want to report to someone without scientific experience.

What are the "world models" LeCun wants to build?

World models are AI systems that learn from video and spatial data (not just text), understand physics and cause-effect relationships, and can plan and reason. According to LeCun, this is what's needed for true artificial intelligence, not current LLMs.

Who is Yann LeCun and why is he important?

LeCun is one of the three "Godfathers of AI," winner of the 2018 Turing Award, and inventor of convolutional neural networks (CNNs) that are the foundation of image recognition today. He worked 12 years at Meta as Chief AI Scientist.

What is AMI Labs?

Advanced Machine Intelligence Labs is LeCun's new startup, based in Paris, seeking a $5 billion valuation to build "world models." The CEO is Alex LeBrun and LeCun is Executive Chairman.

Why does he say LLMs are a dead end?

According to LeCun, LLMs like ChatGPT and Claude are "disembodied mimics" that auto-complete text but don't understand the world. They're good with language but can't reason about physics or causal relationships, making them unsuitable for superintelligence.