Critical Reasoning: Find the Gap
Critical Reasoning tests whether you can locate the logical gap between evidence and conclusion. Every argument has premises (evidence) and a conclusion (the claim). Your job is to name the assumption that bridges them.
Concepts to master
- Conclusion identification: ask "what is the author trying to convince me of?" The conclusion is the claim, not the data.
- Assumption: an unstated premise the argument needs. Negate it-if the argument collapses, it's necessary.
- Question types: strengthen, weaken, assumption, inference, paradox, and evaluate. Each has a distinct move.
Traps that recur
- Out-of-scope comparisons: answers that introduce a new group or variable the argument never discussed.
- Reversal: a choice that weakens when you need to strengthen (or vice versa). Read the question stem twice.
- Attacking the premise: premises are given as true; only the reasoning is fair game.
- Percent vs. absolute numbers: a classic bait in statistics arguments.
Rule of thumb: the negation test
For assumption questions, negate the answer choice. If the negated version destroys the argument, the original is a required assumption.
Worked example
Argument: "Sales rose after we changed the logo, so the logo caused the increase." Negate a candidate assumption-"nothing else changed during that period." If other factors did change, the causal claim fails. So that assumption is necessary. A choice about competitors' logos is out of scope.