U.S. 6-month pause
Six-month training pause. The 2023 letter's ask, for U.S. labs: no training beyond today's frontier for six months.
What it does
No U.S. lab may train an AI system more powerful than today's best for at least six months. This is what the 2023 open letter asked for. China is not bound by it.
Applies to: Training of systems more powerful than the current frontier.
- All AI labs immediately pause for at least six months the training of AI systems more powerful than GPT-4 (the frontier at the time).
- The pause should be public and verifiable and include all key actors.
- If it cannot be enacted quickly, governments should step in and institute a moratorium.
Where things stand
Proposed on March 22, 2023 by the Future of Life Institute letter, which now shows more than 31,000 signatures. Not enacted anywhere. Training did not pause.
Why it costs ~7 weeks
Six months without large training runs. Research continues and labs partly catch up after the pause, so a year later America is about a month and a half behind where it would have been. At the pause's end the gap is larger.
Biggest unknown: Whether it ends when it says it ends.
Why it lowers p(doom) by ~0.2%
Buys six months for safety research to catch up with AI capabilities.
Six months gives safety research a head start on the next generation of models, and shows labs can stop. But labs partly catch up afterward and China keeps going, so the lasting effect is moderate. A rush after the pause could even add risk.
The strongest case that it costs more
The letter asked for a pause by every key actor, including China. If that happened, the lead cost is zero by definition. It did not happen and would not. As a unilateral policy, this is the most expensive item on the menu and the steelman for a higher price is that "at least six months" has no upper bound.
The debate
For
- Future of Life Institute wrote the 2023 open letter calling for a pause of at least six months, now with more than 31,000 signatures.
- Elon Musk, Steve Wozniak, Yoshua Bengio, Stuart Russell were among the letter's best-known signers, 2023.
- PauseAI campaigns to stop development of the most powerful general AI systems until they can be made safe.
- Sen. Bernie Sanders and Rep. Greg Casar introduced a bill to pause advanced AI development until a new federal regulator is running, September 2026.
Against
- Bill Gates said asking one group to pause doesn't solve the challenges, 2023.
- Yann LeCun and Andrew Ng held a public talk titled Why the 6-month AI Pause is a Bad Idea, 2023.
Sources
Rough starting points, not precise forecasts. Lead costs assume China doesn't depend on U.S. models, the case least favorable to safety laws, and count 3 years. On the menu you can change every assumption and put in your own numbers. Last priced 2026-09-26.