Fallacies & Critical Thinking

Fallacies (& Biases?)

Fallacies in General

  • The Fallacy Files is a fantastic site, housing an alphabetical index of well over a hundred different fallacies, along with explanations and examples.
  • The IEP's entry on fallacies is here. It includes a long list of fallacies and descriptions thereof.
  • Spencer Greenberg's site, Clearer Thinking, hosts mini-courses designed to teach you to avoid key fallacies.
  • The SEP has this critical discussion of "Fallacy Theory" (an approach to informal logic that emphasises the detection and avoidance of fallacies).
  • The following video from Kevin de Laplante is about what it is for an argument to be fallacious:

Ad Hominem

  • The following clip outlines the fallacy:

Fallacy of Composition

  • Paul Henne (grad student at Duke University) explains the fallacy in this wiphi clip:

Fallacy of Division

  • Paul Henne (Grad student at Duke University) explains the fallacy in this wiphi clip:

Gambler's Fallacy

  • This clip is a short intro to the gambler's fallacy:

The Red Herring Fallacy

  • The following clip outlines the fallacy:

The Slippery Slope

  • The following clip outlines the fallacy:

The Strawman Fallacy

  • The following clip outlines the fallacy:

The Texas Sharpshooter Fallacy

  • S Peter Davis gives his take on the Texas Sharpshooter fallacy in this clip:

Critical Thinking in General

The Barnum Effect (or Forer effect)

  • Derren Brown...

  • Brian brushwood...

The Burden of Proof

  • This clip very nicely lays out the idea that the burden of proof falls on the person making a claim, not the skeptic. (the main example dealt with is the claim that God exists:

Confirmation Bias

  • The below YouTube clip provides a slightly cruel illustration of our tendency to perceive what we expect to perceive rather than what is really there.
  • The next clip demonstrates how confirmation bias can have horrific consequences:

The Ideomotor Effect

  • Clever Hans
  • The Skeptic's Dictionary entry on Clever Hans effect is here.

Memes and Mind Viruses

  • Key writings on memes and mind viruses include:
    • Richard Dawkins (1991), Viruses of the Mind: here. (The is the article in which Dawkins coined the idea of a "mind virus".)
    • Susan Blackmore (2010), Dangerous Memes; or, What the Pandorans Let Loose: here.
    • Susan Blackmore (2011), Evolution and Memes: The human brain as a selective imitation device: here.
  • Useful sites:
  • The following clip from the Open University's "60 Second Adventures in Religion" series introduces Richard Dawkin's claim that religions are mind viruses:
  • The next video is a TED talk by Susan Blackmore, on memes and temes:
  • And next is a another TED talk, by Daniel Dennett, on memes and mind viruses:


Change Blindness
  • Useful links:
    • The Skeptic's Dictionary entry on change blindness is here.
    • Go Cognitive has this demo of change-blindness.
  • The following clips neatly demonstrate the phenomenon:
  • For more on the colour changing card trick click here.
False memories


  • In this TED talk, magician Keith Barry demonstrates how easy it is to manipulate the human mind once you know how:
Gradual change
  • The following video illustrates the difficulty of detecting gradual change.
  • Visual illusions striking demonstrate the limited trustworthiness of the human perceptual apparatus. Check out NotNotPhilosophy's bespoke illusions site.
  • This clip from the Royal Institution is about building an Ames room:
Inattentional Blindness
  • The following video illustrate inattentional blindness.


  • Videos: