
Slippery Slope Fallacy
“If I let you get away with scribbling on your desk, you’ll start spray-painting the walls next, and eventually you might burn down the school!”
You commit the slippery slope fallacy when you assume that if you allow one thing to happen, it will lead to an inevitable and ultimately disastrous chain of events.
The slippery slope fallacy is tricky to identify because slippery-slope arguments are not always fallacies. Sometimes actions really do create a snowball effect.
If the proposed disastrous outcome seems exaggerated and very unlikely, and the speaker cannot provide concrete evidence for the first step leading down the slope, it’s likely a fallacy.
Let’s compare two slippery-slope arguments—a rational one and a fallacy:
“You should not try highly addictive drugs because this could lead to addiction.”
This is not a fallacy because there is plenty of evidence that certain drugs have high addiction potential. We know how they affect the brain chemically. The progression from trying an addictive drug to becoming addicted has been observed and studied extensively. Although the progression isn’t guaranteed, it is likely enough to warrant caution.
“If you let your child stay up until midnight on New Year’s Eve, they will ask to stay up late on other nights, and this will lead to the complete abandonment of sensible sleeping times.”
This chain of events is very unlikely and highly preventable through responsible parenting, so this argument is a fallacy.
Back to the Logical Fallacy Handbook
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