As an educational service here at OTB, I thought it might be useful to elucidate one of the more common logical fallacies: the fallacy of guilt-by-association. This is also sometimes known as the “Bad Company” fallacy.
The typical structure of an argument that incorporates the guilt-by-association fallacy is something along the lines of:
Person X supports idea I.
Person X is bad (or believes bad things).
Therefore, idea I is bad.
A more real world example of this might be:
Social security is a state funded old age pension.
Nazis supported state funded old age pensions.
Therefore, social security is bad.
Obviously, this argument is ridiculous, because whether a particular person or group supports an idea is irrelevant to the actual merits of the proposal.
Sometimes, this argument goes even further to suggest that support for an idea agreed to by a bad person or group means that anyone who supports the idea is a part of that group or agrees with their ideas. An example of this might be:
The Nazi Party supported building a large, national highway system.
President Eisenhower supported building a large, national highway system.
Therefore, President Eisenhower was a Nazi.
The flaw in the reasoning is clear at this point, too. Acceptance of a particular idea does not mean that one is a member of every group that accepts that idea.
Another variant of this logical fallacy is as follows:
Jeff Albertson voted for Arnold Schwarzenegger for governor.
Jeff Albertson believes that the Vulcan ritual of pon farr should enacted into law.
Therefore, Arnold Schwarzenegger believes that pon farr should be enacted into law.
As you can see, this demonstrates the same type of fallacious reasoning–in this case, one person’s support for a particular candidate must indicate that the candidate holds the exact same ideas, which is clearly spurious reasoning.
I hope you enjoyed this foray into some logical theory for today. Feel free to apply this lesson in your everyday life, not to mention your day-to-day thinking about current events. See you next time!









