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Confusing cause and effect

The logical fallacy of confusing cause and effect is the fallacy of assuming that because things normally occur together one is the cause of the other. Sometimes the term confusing cause and effect fallacy and post hoc fallacy are used interchangeably, but strictly speaking the post hoc fallacy reverses cause and effect, where as confusing cause and effect would also include cases where there is a cause common cause of both events.


  1. Whenever I go outside Jim goes outside too. He went outside when I went to the ice-cream van, and when I left to go to school, so he must be copying me.
  2. At night time the street lights come on. This makes the sun go down. (this is also a post hoc fallacy).
  3. When we sell more hot drinks we sell less sodas. I make more money from selling sodas, so if I put people off buying hot drinks I will sell even more sodas and make more money. (It could be that in hot weather people buy sodas and in cold weather hot drinks, so decreasing sales of one would not increase sales of others despite the seeming correlation).