In April 2026, Yann LeCun responded on LinkedIn to a charge that he had failed to credit Juergen Schmidhuber for foundational world-models work during a lecture at Brown University. His response was blunt: "I did not 'invent' world models, and neither did Juergen." He attributed the lineage to optimal control theorists in the late 1950s and early 1960s, compiled in the 1975 Bryson and Ho textbook. He cited Nguyen and Widrow's 1990 IJCNN paper on differentiable neural networks for control as preceding Schmidhuber's own work. And he closed with a line that is either a mic drop or a provocation, depending on who you ask: "Ideas are a dime a dozen. Showing how to make them work is what really matters." Schmidhuber's position, laid out in a March 2026 IDSIA technical note titled "Who invented JEPA?", is more specific than "I invented world models." He claims three things.…