I don't think that she knows who Adam Smith was. - Charlie Munger

When Warren lectures at business schools, he says, “I could improve your ultimate financial welfare by giving you a ticket with only 20 slots in it so that you had 20 punches, representing all the investments that you got to make in a lifetime. And once you’d punched through the card, you couldn’t make any more investments at all.” He says, “Under those rules, you’d really think carefully about what you did, and you’d be forced to load up on what you’d really thought about. So you’d do so much better.

Stay within a well-defined circle of competence.

If you skillfully follow the multidisciplinary path, you will never wish to come back. It would be like cutting off your hands.