A breakthrough AI study from Apple says frontier AI models that reason, like ChatGPT o3, can’t actually reason at all.

A new study by Apple has ignited controversy in the AI field by showing how reasoning models undergo 'complete accuracy collapse' when overloaded with complex problems.

Days before WWDC 2025, Apple researchers published a paper called The Illusion of Thinking (PDF) that made waves. The researchers wrote that popular and buzzy AI models “face a complete accuracy collapse beyond certain complexities,