Analytical Techniques: Spotting Fallacies in Arguments

Impeccable logic + pointy ears wins arguments but does not necessarily help win the hearts of supermodels.
Impeccable logic + pointy ears wins arguments but does not necessarily help win the hearts of supermodels.

Summary:  We present a handy chart that an Alert Reader passed along with the most common logical fallacies in building arguments.  If you master and apply the material on this one page, you will amaze and impress (and probably also intimidate) your friends with your brilliance.  And by being able to spot errors in others’ analysis, you win the right to denounce their work with an air of haughty derision, and you spare yourself the embarrassment of potentially spouting inaccurate twaddle if you believe what they said.

Fair disclosure, though: your new-found command of logic may not make it easier for you to hit on supermodels (whichever flavor is most appealing to you) in trendy Manhattan clubs.  Don’t ask me how I know this.


An example of a Dadaist logical fallacy in action.
An example of a Dadaist logical fallacy in action.

The first place to check: One of the most important things to do in analysis is to spot fallacies in your own reasoning and in that of others.  It takes a lot of time to nitpick through all the data, making sure it is accurate and relevant to the argument.  But it is often not necessary, because logical flaws can undermine an argument and they’re usually much faster to spot.  

To become a more powerful writer, if you look for fallacies when you edit your work before publishing it, you can save yourself tons of embarrassment when one of your Alert Readers catches you at it.  And you will discover that you become more persuasive, as well.  Even if your readers don’t formally deconstruct your logic, people have enough understanding of logic that they’ll feel uncomfortable about your argument, even if they can’t specifically name the particular fallacy you used.

Honest mistakes:  Sometimes, people make honest mistakes in the way they construct an argument. That’s especially true in areas where people have a high degree of personal involvement, emotional or economic, to a particular outcome.

To make sure you don’t do this, it’s wise to learn the art of clearing your mind and pretending that you’ve never seen the document before that you just wrote.  If you can pretend that you’re about to edit someone else’s writing, it’s a lot easier to step out of the passion that guided you to write something, which may obscure logical flaws in your argument.  Passion is actually welcome in analysis, because it reflects the analyst’s level of conviction in his thesis, but it is only effective when it surfs on top of a logical and well-constructed argument.  Passion on top of logical idiocy gives political speech like we have today.

In the 1970s, Supertramp, which was a way cool band of the time, had a hit with "The Logical Song."
In the 1970s, Supertramp, which was a way cool band of the time, had a hit with “The Logical Song.”

Dishonest mistakes: Other times, people will intentionally use logical fallacies to “sell” a point of view that wouldn’t be supported by evidence. This is particularly common in politics. For example, many news organizations strive to report balance by reporting the political opposition’s view of a circumstance. When Democrats accuse Republicans of something, in many cases, Republicans will reply by talking about how Democrats do the same thing, or something they believe is worse. That’s a logical fallacy, and once you recognize it, it’s possible to keep the attention focused on the matter at hand.

Dilbert gets the relationship between logic, strategy and leadership right... as usual...
Dilbert gets the relationship between logic, strategy and leadership right… as usual…

How to Lose the Argument Before it Begins

There are several different categories of logical fallacies, relating to:

  • The structure of the argument (i.e., whether the reasoning to get from the evidence to the conclusion) is correct;
  • The evidence used in construction of the argument (too much anecdote, too little, etc.);
  • Intentional or willful distractions from a flawed argument (attacking the speaker, etc).

People intuitively know that an argument via an ad hominem attack is inherently a confession that the argument probably doesn’t have enough weight to stand on its own.  Few people are ever convinced by such argument that weren’t already true believers.  That’s why, though I may make legitimate mistakes in logic, I work very hard to avoid any of this deceitful, intentional reasoning error in anything I write.

And Now… The Poster!

Here’s the site: https://yourlogicalfallacyis.com

Here’s the poster: 

A great poster listing many of the common logical fallacies that people either intentionally or accidentally use in logical arguments.  From http://www.yourlogicalfallacyis.com. Click to show full-resolution image.
A great poster listing many of the common logical fallacies that people either intentionally or accidentally use in logical arguments. From http://www.yourlogicalfallacyis.com. Click to show full-resolution image.