Dirac too

seems to be a victim of his intellectual prejudices. From the review Silent Quantum Genius By Freeman Dyson
"The doctrine of mathematical beauty is itself beautiful, and there is no doubt that Dirac believed it to be true. But it does not agree well with the historical facts. During the wonder years when he was making his great discoveries, his thinking was more concerned with practical details and less with abstract beauty. And during the long second half of Dirac's life, when he was preaching the doctrine of mathematical beauty, it did not lead him to important new discoveries.

During Dirac's middle years, the grand edifice of modern particle physics was growing up around him, with discoveries of new particles and new symmetries bursting out in rapid succession. Nature was screaming at him to pay attention to her revelations. But his love for abstract beauty told him to stay aloof. He ignored the new discoveries of particles and symmetries, because he judged them to be too complicated, not beautiful enough to be true. Instead of listening to Nature, he was telling Nature how to behave. As a result, the second half of his life was comparatively sterile."