Understanding your portfolio as a system
A portfolio is more than the sum of its parts. The way individual holdings interact — through shared macro exposures, correlated business models, or overlapping assumptions about the future — determines much of the real-world behaviour of your overall position. Understanding those interactions is one of the most underused skills in private investor research.
These resources cover the core concepts of portfolio-level thinking: how to map the assumptions that run across multiple holdings, how to identify where concentration is building in ways that may not be obvious from a simple sector breakdown, and how to use scenario analysis to stress-test the portfolio as a whole rather than position by position. Each guide is designed to be read alongside an active research session rather than in the abstract.
Examining assumptions and managing uncertainty
Every investment thesis rests on assumptions — about a company's competitive position, about the direction of a market, about the behaviour of management, about the macro environment. Most of those assumptions are never written down, which means they are never properly examined. The practice of making assumptions explicit is one of the most powerful things a private investor can do to improve the quality of their decisions.
The guides in this section explain how to identify the assumptions embedded in a thesis, how to rank them by importance and fragility, and how to think about what evidence would cause you to revise them. They also cover the related discipline of risk examination: not the generic risk warnings that appear in every financial document, but the specific, thesis-level risks that are most relevant to your actual positions.
