Rabbi Judah the Prince — redactor of the Mishnah around 200 CE — and his colleague Rabbi Chiya once found themselves stuck on a point of halakhah. They had forgotten a teaching, or perhaps it had been muddled in transmission, and neither of them could reconstruct it.
The only person in town who remembered the halakhah clearly was a local kobes — a launderer, a man who worked with soap and water in a small shop, and whom the sages had, earlier in their careers, dismissed as unlearned. He was not a rabbi. He held no title. His hands smelled of lye, and his workday had no blessing over books.
But he had listened carefully in the synagogue across many years, and he knew the teaching that Judah and Chiya had forgotten. The two sages humbled themselves to go to his workshop and ask. He instructed them patiently, and they refreshed their knowledge from his mouth.
Gaster's Exempla of the Rabbis (1924, No. 274) preserves this brief note precisely because it was embarrassing. The tradition did not hide it. The compilers of the Mishnah, who sat at the summit of Jewish scholarship, had underestimated a workman and had to walk to his shop to learn what they had lost. Torah does not belong to the titled — it belongs to whoever pays attention.