Speculation is often maligned as mere gambling, but it is a critical component for price discovery, liquidity, and risk transfer in any healthy financial market. Without speculators, markets would be inefficient. Prediction markets are an explicit tool to harness this power for accurate forecasting.

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.

Contrary to popular belief, the market may be getting less efficient. The dominance of indexing, quant funds, and multi-manager pods—all with short time horizons—creates dislocations. This leaves opportunities for long-term investors to buy valuable assets that are neglected because their path to value creation is uncertain.

Contrary to the belief that mega-cap stocks are efficiently priced, behemoths like Alphabet can see 100% price swings in a single year. This volatility creates massive opportunities for patient investors who ignore market noise and focus on fundamentals.

Post-mortems of bad investments reveal the cause is never a calculation error but always a psychological bias or emotional trap. Sequoia catalogs ~40 of these, including failing to separate the emotional 'thrill of the chase' from the clinical, objective assessment required for sound decision-making.

Post-WWII, economists pursued mathematical rigor by modeling human behavior as perfectly rational (i.e., 'maximizing'). This was a convenient simplification for building models, not an accurate depiction of how people actually make decisions, which are often messy and imperfect.

The primary driver of market fluctuations is the dramatic shift in attitudes toward risk. In good times, investors become risk-tolerant and chase gains ('Risk is my friend'). In bad times, risk aversion dominates ('Get me out at any price'). This emotional pendulum causes security prices to fluctuate far more than their underlying intrinsic values.

Contrary to classic theory, markets may be growing less efficient. This is driven not only by passive indexing but also by a structural shift in active management towards short-term, quantitative strategies that prioritize immediate price movements over long-term fundamental value.

Contrary to popular belief, economists don't assume perfect rationality because they think people are flawless calculators. It's a simplifying assumption that makes models mathematically tractable. The goal is often to establish a theoretical benchmark, not to accurately describe psychological reality.