Logical Reasoning and Problem Solving
What the section tests
Logical Reasoning and Problem Solving tests valid deduction, pattern recognition, ordering, assumptions, and data interpretation. The exam rewards the conclusion that must follow, not the one that merely sounds plausible.
Core rules
- A valid argument follows from its premises even if the premises are factually false; validity is about structure.
- For a conditional if P then Q: P implies Q (modus ponens), and not Q implies not P (modus tollens).
- Invalid forms include affirming the consequent (Q, therefore P) and denying the antecedent (not P, therefore not Q).
- Some means at least one, not all. Do not convert some A are B into all B are A.
- In ordering puzzles, draw a line or table and place fixed items first.
Worked example
If a cadet passes the fitness test, then the cadet joins the field exercise. The cadet did not join the field exercise. Therefore the cadet did not pass the fitness test. This is valid modus tollens: if P then Q; not Q; therefore not P. The invalid version would argue: the cadet joined the field exercise, therefore the cadet passed-this affirms the consequent and need not follow.
Traps
Do not bring in outside knowledge to reject a valid but odd conclusion. Watch for words like only, unless, and all. In syllogisms, check whether the middle term is distributed. In data questions, answer the question asked, not every true statement about the data.