Jeff Aronson warns that prolonged success breeds dangerous overconfidence. When an investor is on a hot streak and feels they can do no wrong, their perception of risk becomes warped. This psychological shift, where they think "I must be good," is precisely when underlying risk is escalating, not diminishing.

Unlike surgery or engineering, success in finance depends more on behavior than intelligence. A disciplined amateur who controls greed and fear can outperform a PhD from MIT who makes poor behavioral decisions. This highlights that temperament is the most critical variable for long-term financial success.

The worst feeling for an investor is not missing a successful deal they didn't understand, but investing against their own judgment in a company that ultimately fails. This emotional cost of violating one's own conviction outweighs the FOMO of passing on a hot deal.

The "Liking-Loving Tendency" causes investors to identify personally with their holdings. They ignore faults, favor associated things, and distort facts to maintain positive feelings. This emotional attachment leads them to rationalize bad news and hold deteriorating assets for too long, destroying capital.

Every investment decision feels uniquely difficult in the present moment due to prevailing uncertainties. This mental model reminds investors that what seems obvious in hindsight (like buying in 2009) was fraught with risk at the time, helping to counter behavioral biases and the illusion of past clarity.

Elite decision-making transcends pure analytics. The optimal process involves rigorously completing a checklist of objective criteria (the 'mind') and then closing your eyes to assess your intuitive feeling (the 'gut'). This 'educated intuition' framework balances systematic analysis with the nuanced pattern recognition of experience.

Moving from science to investing requires a critical mindset shift. Science seeks objective, repeatable truths, while investing involves making judgments about an unknowable future. Successful investors must use quantitative models as guides for judgment, not as sources of definitive answers.

Sequoia's internal data shows consensus is irrelevant to investment success. A deal with strong advocates (voting '9') and strong detractors (voting '1') is preferable to one where everyone is mildly positive (a '6'). The presence of passionate conviction, even amid dissent, is the critical signal for pursuing outlier returns.

The most common financial mistakes happen not from bad advice, but from applying good advice that is mismatched with your individual personality and goals. Finance is an art of self-awareness, not a universal science where one strategy fits all. The optimal path for someone else could be disastrous for you.