What Logical Reasoning Questions Look Like
Logical reasoning tests evaluate your ability to analyze arguments, identify patterns, and draw valid conclusions from premises. Unlike IQ tests that measure abstract problem-solving, logical reasoning tests measure specifically how you think through structured statements and their implications.
The format varies by context. LSAT logical reasoning sections present written arguments and ask you to identify assumptions, strengthen or weaken conclusions, or spot logical flaws, typically 48–50 questions in two timed sections. Employer screening tests use syllogisms (if A then B, all B are C, therefore...) or pattern sequences (figure 1, figure 2, figure 3... what's next?). Assessment centers and graduate admissions (GMAT, GRE) include argument evaluation and statement-conclusion formats. The common thread: you're given information and asked to determine what necessarily follows, what might be true, or what contradicts the given facts.
Time pressure is always part of the challenge. Most logical reasoning sections impose 35 minutes for 25–26 questions, forcing you to work at roughly 80 seconds per question, too fast to overthink, slow enough that careful reading matters. Speed without accuracy is worthless; accuracy without speed leaves questions blank. The winning approach balances both.
Syllogism Questions (Type 1)
Syllogisms are the oldest form of formal logic, dating back to Aristotle. A syllogism has three parts: a major premise (a universal statement), a minor premise (another statement), and a conclusion. Your task is to determine whether the conclusion necessarily follows from the premises.
Example 1: Valid syllogism
- Major premise: All mammals are warm-blooded.
- Minor premise: All dolphins are mammals.
- Conclusion: Therefore, all dolphins are warm-blooded.
This conclusion is valid. If the premises are true, the conclusion must be true. The logic is airtight: dolphins fall into the category "mammals," which falls into the category "warm-blooded," so dolphins must be warm-blooded.
Example 2: Invalid syllogism (affirming the consequent)
- Major premise: All engineers are problem-solvers.
- Minor premise: Sarah is a problem-solver.
- Conclusion: Therefore, Sarah is an engineer.
This conclusion is invalid, even though it sounds plausible. Being a problem-solver is necessary to be an engineer, but it's not sufficient, lots of non-engineers are problem-solvers (teachers, artists, managers). Sarah could be a problem-solver without being an engineer. This error is called "affirming the consequent", you've affirmed the result without proving the cause.
Example 3: Invalid syllogism (weak quantifier)
- Major premise: Some executives are Harvard graduates.
- Minor premise: Some Harvard graduates are entrepreneurs.
- Conclusion: Therefore, some executives are entrepreneurs.
This conclusion cannot be determined from the premises. "Some" is too weak. It's logically possible that the executives who are Harvard graduates are different Harvard graduates from the ones who are entrepreneurs. You'd need "all" or stronger language to draw a conclusion. Syllogism tests hinge on understanding quantifiers: "all," "some," "no," "none," and how they distribute across groups.
Statement-Conclusion Questions (Type 2)
These ask: given a set of factual statements, which conclusion must be true, could be true, or cannot be true? The distinction between "necessarily true" and "possibly true" is critical.
Example 1: Necessarily true vs. possibly true
- Statement: "If a company cuts costs, either quality suffers or profit margins improve. After the restructuring, profit margins improved."
- Which must be true?
- A. Quality suffered during the restructuring.
- B. Quality may or may not have suffered during the restructuring.
- C. The company's profit margins are now the highest in its industry.
The answer is B. The original statement says "either quality suffers OR profit margins improve", this is an inclusive or (both could happen), not an exclusive or (only one). Since profit margins did improve, we know the condition was satisfied, but quality could still have suffered. The statement doesn't forbid both outcomes. Answer A is too strong (not necessarily true), and C invents new information.
Example 2: Matching definitions
- Statements:
- 1. All professional athletes who receive endorsement deals are well-known.
- 2. Some well-known athletes do not receive endorsement deals.
- Which conclusion follows?
- A. All well-known athletes are professional athletes.
- B. Some professional athletes do not receive endorsement deals.
- C. Not all professional athletes are well-known.
The answer is B. Statement 1 says: endorsement deals → well-known. Statement 2 says some well-known people don't have endorsement deals. These two facts together mean some professional athletes (who don't have endorsement deals) still exist, otherwise statement 1 would mean all professional athletes are well-known, contradicting statement 2. Answer A reverses the logic (well-known does not imply endorsement), and C contradicts statement 1 directly.
Pattern Sequence Questions (Type 3)
Pattern questions ask you to induce a rule from a series of figures or symbols. The Wason selection task (1966) is a famous variant where you must identify a rule (e.g., "even numbers on one side, vowels on the other") based on a set of cards. Modern tests use similar logic with geometric shapes, number sequences, or symbolic patterns.
Example 1: Figure sequence
- Figure 1: Circle with 2 internal dots
- Figure 2: Square with 3 internal dots
- Figure 3: Pentagon with 4 internal dots
- Figure 4: ?
Rule: The outer shape gains one side each time (circle = 1 curved line, square = 4 sides, pentagon = 5 sides), and the number of internal dots increases by 1. Figure 4 should be a hexagon (6 sides) with 5 internal dots. The pattern is transparent once you focus on two dimensions independently: shape progression and dot count.
Example 2: Number sequence with multiple operations
- 2, 6, 12, 20, 30, ?
The differences are: 4, 6, 8, 10... an increasing arithmetic sequence. So the next difference is 12, and 30 + 12 = 42. This test requires you to look not just at the numbers themselves but at the gaps between them, the second-order pattern. Many people get stuck by assuming a simple multiplication rule and miss the structure.
Argument Evaluation Questions (Type 4)
These present an argument (premise + conclusion) and ask you to identify its weakness, spot a hidden assumption, or choose how to strengthen or weaken it. These are particularly common on the LSAT and in professional hiring assessments.
Example 1: Identifying a flawed assumption
- Argument: "A study showed that people who take vitamin supplements live longer than those who don't. Therefore, taking vitamin supplements increases lifespan."
- What is the flaw in this reasoning?
- A. The sample size of the study is unknown.
- B. The argument confuses correlation with causation.
- C. Vitamin supplements are expensive.
The answer is B. The argument assumes that because supplement-takers live longer, the supplements caused the longer life. But it's equally plausible that people who take supplements are already health-conscious (they exercise, eat well, see doctors regularly), and those healthier habits, not the supplements, extend their lifespan. This is a classic correlation-vs-causation error. Answer A doesn't address the core flaw, and C is irrelevant.
Example 2: Weakening vs. strengthening an argument
- Argument: "Remote work policies increase employee satisfaction. Our company implemented remote work, and employee turnover decreased by 20%. Therefore, remote work improves retention."
- Which finding would most weaken this argument?
- A. Other companies that implemented remote work also experienced decreased turnover.
- B. In the same year, the company also increased salaries by 15%.
- C. Employees working remotely report higher job satisfaction in surveys.
The answer is B. The argument attributes the 20% drop in turnover to remote work, but if salaries also increased, salary, not remote work, might be the real driver (or both could matter equally). This introduces an alternative explanation, weakening the claim that remote work specifically improved retention. Answer A actually strengthens the argument (adds supporting evidence), and C is consistent with the original claim.
How to Approach Each Question Type
For syllogisms: Draw a diagram. Use circles or brackets to represent categories. Syllogisms work visually, once you see that all dolphins fit inside the mammals circle, which fits inside the warm-blooded circle, the conclusion becomes obvious. Pay close attention to quantifiers ("all" vs. "some") because a single weak "some" can make an otherwise sound argument invalid.
For statement-conclusion questions: Distinguish between "necessarily true" and "possibly true." Ask yourself: "Is there any scenario where the statements are all true but the conclusion is false?" If yes, the conclusion is not necessarily true. Also watch for language tricks: "may," "could," "might" signal possibility, not necessity. Don't add external knowledge, only use what the statements explicitly say.
For pattern sequences: Look for structure on multiple dimensions. Don't assume the simplest pattern is correct. Check whether the rule you've identified holds for all given figures, not just the first few. If you see one rule doesn't work, shift to looking at second-order patterns (differences of differences), ratios, or alternating rules.
For argument evaluation: Separate the conclusion from the evidence. Ask: "Does the evidence logically force this conclusion, or is there another explanation?" Look for hidden assumptions, what must be true for the argument to work? Common traps: confusing correlation with causation, generalizing from a small sample, assuming that because one thing happened before another, the first caused the second (post hoc ergo propter hoc).
Across all types: Read statements exactly as written, without charitable interpretation. If an argument is ambiguous, don't assume it means the most reasonable thing, it might mean something weaker or different. In high-stakes tests, logical flaws are often subtle: "some" instead of "all," an assumption stated as a fact, or a conclusion that requires a premise that wasn't given. Slow down, reread, and verify your answer by checking if it still holds if you alter a single word in the premises.
Ready to test your reasoning? Take our logical reasoning assessment to see how you score on patterns, syllogisms, and argument evaluation.