Prerequisites

A prerequisite is knowledge that must be in place before something built on top of it can be learned well. CF’s distinctive claim is quantitative: your skill at the prerequisites sets an approximate maximum on your skill at what comes after. To a good approximation, you can’t be better at a higher-level topic than at its foundations. So weak prerequisites cap achievable skill, and learning advanced material like CF means continually identifying and shoring up the building blocks beneath your goal.

Prerequisites come in layers (A enables B enables C), with each layer ceiling-limiting the next. CF rejects the common reading of “prerequisite” as a requirement you must finish before proceeding. Instead, partially finish a chunk, build a few layers on it, then revisit — see cycling between topics. The point system model makes this concrete: progress is easy when your skill lags well behind its prerequisites and gets hard as it approaches that ceiling.

Diagnosis is central. When you get stuck or your error rate rises, the cause is usually a missing or under-automatized earlier layer, not the current one — so review earlier layers rather than grinding the current task. This is the foundation of CF’s knowledge skyscraper picture and informs skill-gap management.

CF also insists on testing prerequisites against their purpose: after learning a chunk, use it on a real higher-level task to confirm it actually helps. Because philosophy builds on prerequisites like language and math, targeted, purpose-driven prerequisite work — not exhaustive bottom-up study — is the efficient path.