AI chatbots have become more accessible in recent months — bringing with them a range of ethical concerns.

Even Elon Musk, co-founder of ChatGPT-creator OpenAI, has some reservations. An open letter signed by him and a group of artificial intelligence experts and industry executives is urging a six-month pause in developing systems more advanced than GPT-4, warning against potential threats to society and humanity, Reuters reported.

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The letter, signed by more than 1,000 people, including Musk, was released by the nonprofit Future of Life Institute, which is predominantly funded by the Musk Foundation, the London-based group Founders Pledge and the Silicon Valley Community Foundation, per the European Union’s transparency register.

“AI systems with human-competitive intelligence can pose profound risks to society and humanity, as shown by extensive research and acknowledged by top AI labs,” the letter begins.

The letter goes on to say that further development should only occur when “we are confident” that the impact will be positive and the risks manageable, noting potential economic and political consequences.

According to a 2021 Stanford University report, AI systems are being used to spread disinformation on the internet, which gives them “the potential to become a threat to democracy and a tool for fascism.”

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But some critics have slammed the letter’s signatories for contributing to “AI hype” in an attempt to spike people’s interest in the technology, per Reuters.