What Neil deGrasse Tyson says about silicon-based life and AI

Neil deGrasse Tyson, the astrophysicist who directs the Hayden Planetarium and hosts StarTalk, has been asked about silicon-based life for decades. His answer on the chemistry has been consistent: carbon wins. His views on artificial intelligence are more recent, and more nuanced than a single headline suggests. Here is what he has said, in his own words, with every source linked.

Carbon beats silicon: the 2002 essay

In a 2002 essay for Natural History magazine, “The Periodic Table of the Cosmos,” Tyson took up the classic question. He starts from the resemblance:

“Silicon sits directly below carbon on the Periodic Table allowing it to create the same chemical compounds as carbon except with silicon in its place.”

Then he gives his verdict:

“In the end, we expect carbon to win because it's not only ten times more abundant than silicon in the cosmos, it forms chemical bonds that are substantially stronger.”

He adds that complex molecules based on silicon lack the hardiness to survive ecological stress^↗. That is the same conclusion chemists reached in much more detail years later: silicon’s long molecular chains are fragile, and it binds oxygen so strongly that it ends up locked in solid silica. See the chemistry of silicon-based life.

Tyson ends the passage with a nod to fiction:

“But that doesn't stop science fiction writers, who keep exobiologists on their toes, wondering what the first truly alien life form will be like.”

Star Trek is the obvious example. Its Horta, a silicon-based creature that tunnels through rock, first aired in 1967. See every silicon-based life form in Star Trek.

On StarTalk: silicon aliens and silicon minds

The question keeps coming back on StarTalk, the podcast and show Tyson hosts.

• “Cosmic Queries: Silicon Aliens with David Grinspoon” (January 31, 2023). Tyson and astrobiologist David Grinspoon take listener questions about silicon-based aliens. The conversation covers why silicon’s chemical bonds are stiffer than carbon’s and how much more carbon the universe contains (StarTalk, 2023).
• “Stars Talk to Neil: Alien Love” (April 26, 2024). The hosts discuss the ingredients for life and whether silicon-based life could exist, including a playful exchange about whether today’s silicon chips count (StarTalk, 2024).
• “Is Consciousness Everywhere? With Anil Seth” (January 24, 2025). A debate with neuroscientist Anil Seth about whether consciousness depends on what a system is made of, carbon or silicon (StarTalk, 2025).
• “The Origins of Artificial Intelligence with Geoffrey Hinton” (February 20, 2026). Tyson talks with the Nobel laureate often called a godfather of AI (StarTalk, 2026).

A note on quoting these episodes: StarTalk’s published transcripts do not say which host is speaking. We only quote a line once we have confirmed who said it from the audio. Until then, we describe these conversations rather than quote them.

On AI: useful tools, a dangerous edge

Tyson’s comments on AI fall into three groups.

He is unimpressed by AI writing. Discussing how the questions people ask him have changed, he told CBS Mornings in October 2025:

“If you have ever seen those replies that come in from AI, it's got no soul. It's got no personality.”

He wants limits on superintelligence. In March 2026, TechRadar reported that Tyson wants to ban AI superintelligence, quoting him: That branch of AI is lethal. We've got to do something about that^↗ (TechRadar, 2026).

He rejects treating AI as one thing. Speaking to TMZ in September 2026, amid warnings from AI researchers about extreme risks, he pushed for nuance:

“Don't think of AI as a monolithic thing.”

He continued: There's a lot of AI that's very useful, you know, to fix your spreadsheet, to organize lists.^↗. But, he said, At the edge of AI, there's the stuff that could kill us^↗, and his prescription was specific: Go to the edge and say, 'That's the bad stuff. Put the guardrails there.'^↗ (TheGrio, 2026).

What Tyson’s view means for Silicon-Based Intelligence

Tyson’s position lines up with the distinction this site is built on. As chemistry, silicon-based life looks like a losing bet, and he has said so for more than two decades. As technology, silicon is where machine intelligence lives, and his concern there is not whether it is real but where it becomes dangerous.

That is the difference between silicon-based life, which chemistry argues against, and Silicon-Based Intelligence, which runs on the chips in front of you. Whether the second could ever become a kind of the first is the question we take up in Is AI a silicon-based life form?

This site is not affiliated with Neil deGrasse Tyson or StarTalk. Quotes are drawn from his published writing and from interviews reported by the outlets linked above.