Temporarily accept the premise and examine what follows. An unwelcome outcome alone is not a logical contradiction; show the steps and give the premise a fair reading.
If a team says no project may carry any risk, ask whether that rule also excludes the current strategy. Clarify the acceptable risk threshold rather than demanding an impossible standard.
How It Works
The technique follows a clear logical structure. First, you identify the principle or rule underlying your opponent's position. Then you construct a scenario in which that principle is applied consistently but leads to a conclusion that no reasonable person would accept. The opponent is then forced into a dilemma: either accept the absurd conclusion, or admit that their principle needs qualification, which opens their entire argument to revision.
The distinction between reductio ad absurdum and the slippery slope fallacy is important. A slippery slope argument claims that one event will inevitably lead to a chain of increasingly bad outcomes without demonstrating why each step follows from the last. Reductio, by contrast, does not argue that bad things will happen sequentially. It argues that the principle itself, if applied consistently right now, produces an unacceptable result. The logic is deductive, not speculative.
When to Use It
Reductio is most effective against arguments that rely on broad, unqualified principles. "All taxation is theft," "censorship is always wrong," "the market should decide everything." These sweeping claims are vulnerable because they are designed to sound clean and absolute, but they inevitably break down at the margins. A skilled debater identifies those margins and forces the opponent to confront them.
The technique is less effective against opponents who have already built qualifications into their positions. If someone says "most taxation is unjustified except in cases of clear public benefit," there is less room for reductio because the position already acknowledges exceptions. It is also weaker against audiences that share the opponent's commitments strongly enough that they are willing to accept the "absurd" conclusion rather than abandon the principle.