Every investor knows not to put all your eggs in one basket. So why is Silicon Valley betting on just one way to build artificial intelligence? This year the world’s four largest tech firms will spend $344 billion on AI, mostly on data centers used to train and run so-called large language models (LLMs) like ChatGPT that can process text, audio and visual content. The technology is largely underpinned by the same technique of predicting tokens that appear next in a sequence.