Cognitive Biases: How the Mind Cuts Corners

A cognitive bias is a real, predictable mental shortcut that feels like reasoning while quietly skipping the actual reasoning part. This chapter covers four real, well-documented biases — including one so striking it directly inspired the psychological study that ended up naming it.

Anchoring: A Real, Foundational Study

The Availability Heuristic

People judge how common or likely something is by how easily examples come to mind — not by its actual real frequency. Vivid, dramatic, heavily covered events (plane crashes, shark attacks) feel more common than they really are, while less dramatic but far more common causes of harm (heart disease, car accidents) feel comparatively rare, simply because they're less memorable and less frequently reported.

Sunk Cost: A Real, Named Case

Britain and France's 1962 Concorde supersonic jet agreement eventually cost roughly £1.3 billion in real development spending. Long before the project entered commercial service, both governments privately understood it would never be profitable — rising fuel costs, strict noise regulations, and limited seating made that clear. They kept funding it anyway, in real part because so much had already been spent that stopping felt like admitting the money was wasted. The pattern is common enough that "sunk cost fallacy" has a second real name: the Concorde fallacy.

Dunning-Kruger: A Real, Bizarre Origin Story

That real case directly inspired Cornell researchers David Dunning and Justin Kruger's real 1999 study, "Unskilled and Unaware of It" — establishing that people with genuinely low ability in a given area often lack the specific skill needed to recognize their own incompetence, leading them to rate their own performance far more confidently than it deserves.

Four Biases, Compared

Hands-On Exercises