"For my own part,” Ms. Yellen said, “I did not see and did not appreciate what the risks were with securitization, the credit ratings agencies, the shadow banking system, the S.I.V.’s — I didn’t see any of that coming until it happened.” Her startled interviewers noted that almost none of the officials who testified had offered a similar acknowledgment of an almost universal failure.

Economist and likely future chairperson of the Federal Reserve Board Janet Yellen shows the key rationality trait of being able to admit you were wrong.