Fallacy · Bad evidence
Post hoc
Also called: Post hoc ergo propter hoc, “after this, so because of this”
Assuming that because one thing happened after another, the first caused the second.
What it is
Order in time is easy to see; causes are not. Lots of things follow one another by coincidence, or because something else caused both. A cause needs more than a sequence: a plausible way it works, and evidence that the second thing would not have happened anyway.
An example
“I wore my lucky socks and we won. The socks work.” The team also won plenty of matches without them.
How to spot it
The only link between the two events is that one came first.
How to answer it
“Would it have happened anyway? What else changed at the same time?”
When it is not a fallacy
Order in time is part of any causal case, since a cause must come before its effect. The sequence is fair as a lead to investigate, not as the conclusion.
Printable sheet of all fallacies
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A plain reference you can paste into notes or an essay:
Quest2Reason. “Post hoc.” https://quest2reason.com/learn/ideas/fallacies/post-hoc. Accessed 13 November 2026.