Slippery slope fallacy

The slippery slope fallacy claims that a small change will inevitably lead to a series of more extreme changes, without justifying each step.

Example

“If we allow this, then we will allow that, and eventually we will end in disaster.”
(The chain is not shown to be inevitable.)

Applied example (political)

“If we allow this march, any group will take the streets and we will end in anarchy.” (Intermediate steps are not justified.)

Applied example (mystical)

“If you doubt once, you will lose faith and end in emptiness.” (The chain is not inevitable.)

Why it is fallacious

• It does not prove each intermediate step.
• It exaggerates consequences to block reasonable decisions.
• It ignores controls or limits.

How to spot it

• Long chains of “if A then B” without evidence.
• Logical leaps between stages.
• Catastrophic language without data.

How to respond

• Ask for evidence at each link.
• Show control points or alternative decisions.
• Evaluate the concrete case, not the hypothetical escalation.