Mohnish Pabrai discusses the concept of "circle of competence" in investing, emphasizing that successful investing doesn't require understanding a vast number of industries. Instead, it involves focusing on areas one truly understands and patiently waiting for opportunities within that domain. He uses anecdotes from Warren Buffett and John Arga to illustrate this point, highlighting that consistent learning and curiosity are key to identifying "anomalies" or undervalued investments.