Analytical Reasoning: Deduction, Sequencing, Assumptions and Arguments
Analytical Reasoning tests whether you can derive what must be true from what is given. Items come in three families: formal logic and syllogisms, constraint puzzles (ordering, grouping, scheduling), and argument analysis (assumptions, inferences, strengthening and weakening). The discipline is identical across all three - use only the stated information, and distinguish 'must be true' from 'could be true'.
Conditional logic
The statement 'If P then Q' licenses only its contrapositive, 'If not Q then not P'. The converse ('If Q then P') and the inverse ('If not P then not Q') are invalid. 'P only if Q' also means P → Q. 'Unless' means 'if not': 'Unless it rains, the match proceeds' becomes 'if it does not rain, the match proceeds'. In syllogisms, 'all A are B' does not establish 'all B are A', and 'some A are B' does not establish 'some A are not B'.
Ordering and grouping puzzles
Draw one slot per position and enter fixed facts first. Chain relative rules (A before B, B before C, therefore A before C), then use negative rules to eliminate options rather than to build the full arrangement. Where a rule is conditional ('if F is third, G is fifth'), its contrapositive is equally usable and often the faster route. Test each answer choice against every rule instead of trusting the first plausible arrangement.
Assumptions and arguments
A necessary assumption is the unstated bridge between evidence and conclusion; the negation test exposes it, because denying a true assumption destroys the argument. To weaken, attack the link between evidence and conclusion, not the evidence itself. An inference must follow from the premises, whereas an assumption is something the author left unsaid.
Worked example
'If a file is encrypted, it cannot be opened without a key. This file was opened without the key. Therefore it was not encrypted.' This is valid: it is the contrapositive of the premise. Concluding instead that 'any file opened with a key is encrypted' would be the converse error.
Traps that cost marks
- Affirming the consequent or denying the antecedent.
- Over-inferring beyond the premises, or importing real-world knowledge.
- Ignoring 'exactly once' and 'each used only once' constraints.
- Choosing an option that is possible when the question demands what is certain.