---
title: "Thinking errors"
url: https://erroneo.us/thinking/
description: "Cognitive biases and logical fallacies explained with everyday examples, the research behind them, and practical ways to catch them in yourself."
type: section
section: "Thinking"
date_modified: 2026-10-20
publisher: erroneo.us
license: All rights reserved. Quote with attribution and a link.
---

# Thinking errors

> The mistakes we make before we say a word — and the ones we make the moment we start arguing.

- [Thinking Cognitive biases: the predictable ways good minds go wrong A sourced guide to 20 common cognitive biases: anchoring, confirmation bias, sunk cost, Dunning-Kruger and more, with examples, fixes and replication caveats.](https://erroneo.us/thinking/cognitive-biases/)
- [Thinking Logical fallacies: how arguments break, with examples Straw man, ad hominem, false dilemma, slippery slope, post hoc and more: 20 logical fallacies explained with plain examples, Latin names and how to respond.](https://erroneo.us/thinking/logical-fallacies/)

## Biases vs. fallacies

These two ideas get mixed up constantly, so here is the short version. A **cognitive bias** is a systematic tilt in how people judge or decide: we lean on the first number we hear, we notice evidence that agrees with us, we overrate what is easy to recall. Biases are psychological; they happen whether or not anyone is arguing.

A **logical fallacy** is a defect in an argument: the conclusion doesn’t follow from the reasons given, even if it sounds as though it does. Fallacies are about the structure of reasoning, which is why philosophers, not psychologists, catalogued most of them.

|  | Cognitive bias | Logical fallacy |
|---|---|---|
| What it is | A pattern in judgment | A flaw in an argument |
| Where it lives | In the thinker | In the reasoning as stated |
| Studied by | Psychology, behavioral economics | Logic, philosophy, rhetoric |
| Example | Anchoring on a list price | “Everyone buys it, so it must be good” |

## A note on evidence

Some famous findings in psychology have not held up when other labs repeated them. Where an effect is contested, our guides say so and link the replication work, instead of presenting a classic study as settled. Knowing which errors are well established is itself a guard against error.

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Source page: https://erroneo.us/thinking/ · More: https://erroneo.us/llms.txt