Logical Deduction
Syllogisms, conditional inference, ordering
What this sub-test measures
Logical deduction probes how reliably you can chain premises into valid conclusions while ignoring superficially plausible but logically invalid distractors. Items resemble Wason's selection task, classical syllogisms, and ordering puzzles common to the LSAT logic-games section. Performance on deduction is closely tied to working-memory capacity (how many premises you can hold open at once) and to inhibitory control (the ability to suppress what 'sounds right' in favor of what 'follows'). Strong reasoners diagram the premises before reading the candidate conclusions, and they actively look for counter-models — situations in which the premises hold but the candidate conclusion fails. Deduction overlaps substantially with pattern recognition on g but has its own facet because it is more sequential and less perceptual than matrix reasoning.
Strategy notes
- Diagram the premises before reading the candidate conclusions — paper saves working-memory slots.
- Translate "all A are B" carefully: it does not mean "all B are A". Direction matters.
- For conditional rules ("if P then Q"), test the contrapositive ("if not Q then not P"); it is logically equivalent and often the trick.
- Actively look for counter-examples to candidate conclusions. A single counter-model invalidates a deduction.
- Slow down on items that feel obvious — high difficulty deduction items reward conscious analytical thought over intuition.
Sample items from this domain
Item #81
Apply the rules of logical inference.
View itemItem #82
Apply the rules of logical inference.
View itemItem #83
Apply the rules of logical inference.
View itemItem #84
Apply the rules of logical inference.
View itemItem #85
Apply the rules of logical inference.
View itemItem #86
Apply the rules of logical inference.
View itemTraining drills for this domain
Syllogism Warmup
10 min
Conditional Logic Practice
20 min
Logic Ordering Puzzles
30 min
Wason Selection Task Practice
15 min
Logic-Grid Puzzles
25 min
Daily Morning Brain Routine
20 min
Improve Logical Deduction
See the brain-training guide for Logical Deduction →
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