Logical and Abstract Reasoning
Logical and Abstract Reasoning tests deductive validity, pattern recognition and assumption analysis. Validity concerns structure, not truth: a valid argument can have false premises.
Core rules
- All A are B licenses conversion to some B are A only if A is known to exist; it always licenses the contrapositive no non-B is A.
- Some A are B is reversible (some B are A) but supports no conclusion about all.
- Two some premises yield no valid conclusion; two negatives yield none either.
- In assumption questions, apply the negation test: if negating the option destroys the argument, it is a necessary assumption.
- Seating and scheduling puzzles: fix the most constrained entity first, then place absolutes (ends, floors, days) before relatives.
- Figure series: check rotation, element count, shading alternation and position swap in that order.
- Coding–decoding: test letter shifts, reversal and positional substitution before inventing rules.
Worked example
Premises: All auditors are graduates. Some graduates are pilots. Does "some auditors are pilots" follow? No. The graduates who are pilots may lie entirely outside the auditor subset. The only safe conclusions are "some graduates are auditors" and "some graduates are pilots". Any option asserting overlap between auditors and pilots is a possibility, not a deduction.
Traps
Assuming overlap from some statements; reversing all as all; importing real-world knowledge into formal logic; and in assumption questions picking a strengthening statement rather than a necessary one.