Professor Geoffrey Hinton: The idea of opening up to all humanity sounds like open sourcing. It might be what I mean. But when you open source a big model and give people the weights that's not at all like open weights is not like open source. Open source you get thousands or millions of people looking at lines of code to say wait a minute there's a problem here. You don't get people looking at the weights to say this one should be a little bit bigger. You get people using that open source model and training it, refining it to do something bad like cyberattacks or making biological weapons because it's much easier to refine the model than just to train it. So my belief is that open-sourcing weights is a bit like making fissile material free. The reason we don't all have action problems is because it's hard to get fissile material. There are other problems but the main problem is that it's expensive. Open-sourcing weights is like making fissile material free so I think that's crazy. I think we have to and I don't think we can rely on the big companies. The only route I can see to make it safe against the existential threat is to have people pressure governments to regulate companies and force their companies to do a lot of work on safety. Unverified source (2025)