Post hoc

Post hoc (post hoc ergo propter hoc—"after this, therefore because of this") is when you conclude that because one thing happened after another, the first caused the second. Order in time doesn't by itself mean cause. We're wired to see causes before effects, so we often assume the earlier event was responsible when it was just coincidence or something else was the real cause. The cognitive bias of illusory correlation captures this tendency. The fallacy is to infer causation from sequence alone. Related: Illusory correlation.

Examples

• I wore my lucky shirt and got the job, so my lucky shirt got me the job.

• The rooster crows before sunrise, so the rooster causes the sun to rise.

• We launched the campaign and sales went up, so the campaign worked.

• I took the supplement and my cold went away, so the supplement cured it.