A slippery slope fallacy is an argument that relies on one situation inevitably lead to another when that is not necessarily the case. By relying on the “snowball effect” or “dooms day scenario” a slippery slope argument attempts convince by reasoning that since you don’t want the really bad outcome, then you also don’t want the thing that could eventually lead to the really bad outcome to happen either.

Essentially slippery slope fallacies take the form of:
• Premise: X has occurred (or will occur)
• Conclusion: Therefore y will inevitably happen

 
OR

• Premise: If A then B
• Premise: If B then C
• Premise: If C then D
• Conclusion: Therefore E

 
It is in this way that slippery slope fallacies rely on emotions and assumptions (that you may also have or may not question). These types of arguments can often persuade by distraction: you may be fearful of the worst possible outcome and therefore accept the argument.

However, it is important to realize that this type of argumentation is flawed because it is often the case that doing the first thing will not necessarily result in the bad thing happening. This is because slippery slope fallacies rely on unreasonable assumptions and claims about cause and effect that can be easily disproved. All it takes is to find one good reason why one action does not in fact always lead to another action.

Example Argument: We shouldn’t allow the tuition to be increased every year because eventually this will result in tuition to be $500,000 a semester!

It is not necessarily the case that if tuition increases yearly that it will get so out of hand that it will be raised to $500,000 a semester. It is equally as possible to think that tuition will increase slowly and at a reasonable rate.