Learn the why. Not just the what.
Investing fundamentals, market logic, and the discipline behind good decisions.
Market Efficiency: What the Theory Does and Does Not Claim
The efficient market hypothesis may be the most misrepresented idea in finance: attacked for claims it never made, and defended for conclusions it doesn't actually support.
The Mathematics of Leverage: Why Borrowing Cuts Both Ways
Leverage magnifies returns, which sounds great until you notice it magnifies losses just as reliably, and introduces a danger that has no equivalent on the way up.
Reflexivity: When Prices Change the Reality They Reflect
Usually a price reflects reality. Sometimes the price becomes part of the reality it is supposed to reflect, and the ordinary relationship between the two falls apart.
Risk and Return: Why the Two Cannot Be Separated
Wanting high returns without risk is the most common wish in investing, and the most dangerous. It doesn't just fail to come true. It describes something that cannot exist.
Sector Rotation: Why Different Parts of the Market Take Turns
At any given moment, parts of the market are thriving while others struggle, and leadership passes from one to another in ways that look obvious afterward and invisible beforehand.
The Spread: The Cost You Pay Without Being Told
Commissions are visible, and these days often zero. The spread is invisible and never zero, and across enough trades, it's the bigger cost of the two.
Timeframes and Self-Similarity: Why the Same Patterns Appear at Every Scale
A price chart of a single day and one of a decade can look strikingly alike. That resemblance isn't coincidence, and it has real consequences for how markets should be read.
Volatility Is Not Risk: A Distinction That Changes Everything
Volatility measures how much a price moves. Whether that movement amounts to risk depends on something volatility itself can't tell you: how long you actually plan to hold.
What a Share Price Actually Represents
A price isn't a measurement of what something is worth. It's a record of what one buyer and one seller managed to agree on, in the last moment they agreed on anything.
Who Is on the Other Side of Your Trade
Every purchase needs a seller. Before congratulating yourself on an insight, it's worth asking who took the other side, and why.
Why a Company Can Report Excellent Results and Fall
A company posts record profits and its stock drops. Nothing has gone wrong. The market wasn't reacting to the profits, it was reacting to the gap between the profits and what everyone…
Why Markets Are Hard to Beat: The Competition You Cannot See
When you buy because you think something is cheap, someone else is selling because they think it is dear. The uncomfortable question is what that someone knows that you do not.
Position Trading vs. Long-Term Investing
Position trading holds for months on a view about conditions; long-term investing holds for years on a view about businesses. The similarity of their timeframes conceals a fundamental difference in reasoning.
Swing Trading: Understanding It Without Being Seduced by It
Swing trading seeks to capture price movements over days or weeks. It demands genuine discipline, and it is frequently adopted by people who mistake its accessibility for ease.
Day Trading: What the Data Actually Says About the Odds
Studies across multiple countries and decades have found that the large majority of day traders lose money, and that persistent profitability is confined to a very small minority.
Trend Following: A Rules-Based Way to Stay Humble
Trend following is a systematic style that responds to established price movements rather than forecasting them. Its virtue is the abandonment of prediction; its cost is frequent small losses.
Style Drift: How Investors Quietly Abandon Their Own Plan
Style drift is the slow erosion of a stated framework through small, defensible exceptions. It is rarely a decision and almost always the accumulation of many.
Choosing a Style That Fits Your Temperament
A style only works if it is sustained, and sustainability depends on temperament far more than on the theoretical merits of the approach.
Why Copying Someone Else's Style Usually Fails
A style cannot be separated from the circumstances, horizon, and temperament of the person who built it. Copying the visible decisions while lacking the invisible foundation is a recipe for abandonment.
Concentration vs. Diversification as a Style Choice
Concentration expresses confidence in one's analysis; diversification expresses humility about it. The choice between them is a claim about the reliability of one's own judgement.
The Role of Cash in Every Investing Style
Cash serves as reserve, optionality, and psychological ballast. Its cost is real and its function is misunderstood by investors who evaluate it only on the return it fails to produce.
Rebalancing: The Style-Agnostic Discipline
Rebalancing restores a portfolio to its intended proportions, preventing unintended concentration. It is mechanically simple and psychologically difficult, which is the whole of its story.
How Market Regimes Reward Different Styles
Market conditions favour different styles at different times, and no approach is rewarded continuously. Recognising this pattern is what makes it possible to endure a style's difficult periods rather than abandoning them.
Blending Styles Without Losing Coherence
A deliberate blend of styles requires that each component have a defined role and a defined proportion. Without that structure, blending becomes indistinguishable from having no framework at all.