Skip to content
a16za16z

The Next Frontier of AI Is Spatial Intelligence | Fei-Fei Li on a16z

Last week, World Labs announced its acquisition of SceniX, bringing together two teams working on one of AI's biggest unsolved problems: how to give machines a true understanding of the physical world. Martin Casado sits down with Fei-Fei Li, co-founder and CEO of World Labs, creator of ImageNet, and pioneer of spatial intelligence, alongside Yunzhu Li, co-founder of SceniX and assistant professor at Columbia University. They discuss why World Labs acquired SceniX, how simulation can unlock the next generation of robotics, and why training robots may require a fundamentally different approach than training language models. The conversation explores real-to-sim-to-real pipelines, world models, robotics foundation models, evaluation, synthetic data, and why the future of AI depends not just on understanding language—but on understanding and interacting with the physical world. Timestamps: 00:00 - Intro 01:08 - World Labs & SceniX 06:04 - Marble & the Data Bottleneck in Robotics 07:13 - How the Two Teams Come Together 10:55 - Building a Foundation Model for Robotics 12:35 - Video Models vs Real-to-Sim-to-Real 19:38 - Why Simulation is Essential for Robot Learning 23:01 - Training, Evaluation & Real Customer Use Cases 29:17 - Humanoids, Semi-Structured Environments & the Grand Challenge 36:56 - Integration Plans & What Success Looks Like in Two Years Resources: Follow Fei-Fei Li on X: https://x.com/drfeifei Follow Yunzhu Li on X: https://x.com/YunzhuLiYZ Follow Martin Casado on X: https://x.com/martin_casado Stay Updated: If you enjoyed this episode, be sure to like, subscribe, and share with your friends! Find a16z on X: https://twitter.com/a16z Find a16z on LinkedIn: https://www.linkedin.com/company/a16z Listen to the a16z Show on Spotify: https://open.spotify.com/show/5bC65RDvs3oxnLyqqvkUYX Listen to the a16z Show on Apple Podcasts: https://podcasts.apple.com/us/podcast/a16z-podcast/id842818711 Follow our host: https://x.com/eriktorenberg Please note that the content here is for informational purposes only; should NOT be taken as legal, business, tax, or investment advice or be used to evaluate any investment or security; and is not directed at any investors or potential investors in any a16z fund. a16z and its affiliates may maintain investments in the companies discussed. For more details please see http://a16z.com/disclosures.

Fei-Fei LiguestYunzhu LiguestMartin Casadohost
Jul 28, 202642mWatch on YouTube ↗

At a glance

WHAT IT’S REALLY ABOUT

Fei-Fei Li explains spatial intelligence powering real-to-sim robotics foundation models

  1. World Labs frames “spatial intelligence” as the next AI frontier: models that understand, generate, and reason about 3D spaces and interactions across physical and virtual worlds.
  2. SceniX tackles robotics’ core bottleneck—scarce, slow, costly real-world data—by mapping real environments into aligned digital twins for scalable training and evaluation (real-to-sim-to-real).
  3. Their synergy centers on Marble, World Labs’ base model that generates geometrically consistent 3D worlds from prompts, enabling more efficient environment reconstruction and simulation infrastructure.
  4. The discussion argues simulation is essential (not optional) because it enables counterfactual reasoning, systematic coverage of edge cases via randomization, and faster iteration than real-world robotics testing.
  5. They outline a pragmatic go-to-market: serve near-deployment customers in semi-structured environments (warehouses, assembly, hospitality) and measure success via lighthouse customers and proven automation value within two years.

IDEAS WORTH REMEMBERING

5 ideas

Robotics needs “world understanding + action,” not just perception.

World Labs positions spatial intelligence as the capability to generate and reason about 3D space, while a robotics foundation model likely must also model actions—both as inputs (forward simulation) and outputs (policy).

Marble’s value is geometrically consistent 3D worlds from sparse input.

Marble converts text/images into consistent 3D representations (e.g., Gaussian splats/meshes), which SceniX can leverage to make environment reconstruction and simulation setup more efficient and scalable.

Simulation is a scaling unlock because real-world robotics data is fundamentally constrained.

Unlike internet-scale language data, robotics requires moving atoms under physics, making collection slow, dangerous, and expensive; simulation provides a lever to approximate scaling laws via synthetic generation and faster iteration.

Consistency across time, viewpoints, and interactions is where video-only approaches often fail.

Yunzhu contrasts their approach with video prediction models that can violate object permanence or interaction logic; a robot learning world must remain stable under actions to produce trustworthy training signals.

The right goal is not perfect fidelity, but “essential structure” plus systematic randomization.

They argue effective sim-to-real can work without modeling every bush or surface precisely, as long as the simulator captures key dynamics and uses controlled variation (lighting, friction, geometry) to build robustness.

WORDS WORTH SAVING

5 quotes

We are building the next frontier of AI, which is what we call spatial intelligence.

Fei-Fei Li

Think about human intelligence. We do a lot of simulation in our head. You know why? There's a very important role simulation plays that real world data doesn't play, which is counterfactual reasoning.

Fei-Fei Li

What we are building is a consistent world. Consistent both over space, over time, over different viewpoints, and over different type of interactions. My North Star is I want the robot to work.

Yunzhu Li

I want to add to this and be s- uh, slightly philosophical here, is there isn't a, a, uh, binary choice between simulation or no simulation. All this come, um, in together, um, to, to make robotics work.

Fei-Fei Li

Martin, the hardest thing in today's AI is to have the right measured optimism.

Fei-Fei Li

Spatial intelligence and large world modelsMarble generative 3D world generationRobotics data bottleneck (training + evals)Real-to-sim-to-real pipeline and digital twinsConsistency vs video-only world predictionSimulation benefits: counterfactuals, reliability, efficiencyDeployment focus: semi-structured environments; measured optimism

High quality AI-generated summary created from speaker-labeled transcript.

Get more out of YouTube videos.

High quality summaries for YouTube videos. Accurate transcripts to search & find moments. Powered by ChatGPT & Claude AI.