What is the next number? 2, 6, 12, 20, 30, __ (Answer: 42 – differences increase by 2 each time: +4, +6, +8, +10, +12.)
The beauty of logical questions is that they do not require advanced mathematics or specialized knowledge—only discipline, attention, and a willingness to question the obvious. The 100 questions are divided into five distinct categories, each targeting a specific facet of logical reasoning. The difficulty progresses from warm-up exercises to expert-level paradoxes. Category 1: Syllogisms and Deductive Reasoning (Questions 1–20) Focus: Validity of arguments, "All men are mortal" structures.
You see two people. C says: "D and I are both knaves." What are they? Solution: Impossible if C is a knave (both knaves would make the statement true). So C must be a knight. But then both must be knaves – contradiction. Therefore, this is a paradox; no consistent assignment exists. (Excellent for spotting impossible premises.) 100 Pyetje Logjike
"You can't trust his opinion on climate science because he drives a gas-powered car." What fallacy is this? (Answer: Ad hominem – attacking the person's behavior instead of the argument.)
A judge says: "You will be hanged at noon on a weekday next week, but the hanging will be a surprise." The prisoner reasons it cannot be Friday, then Thursday, etc., concluding no hanging – yet it happens on Wednesday, surprising him. Where is the flaw? (Note: This question has no single answer but invites discussion of epistemic logic.) What is the next number
These questions encourage intellectual humility – sometimes logic reveals limits. | Approach | Recommendation | |----------|----------------| | Solo practice | Set a timer: 2 minutes per question. No peeking at answers. | | Group discussion | Debate answers – logic is sharpened by disagreement. | | Daily habit | Do 5 questions per day. Consistency > intensity. | | Error log | Track which categories you fail most. Revisit those. | Sample Questions with Solutions To give a taste, here are three authentic problems from the collection:
These questions train the user to separate logical necessity from probability. Focus: Boolean logic, binary states, self-referential statements. C says: "D and I are both knaves
This category is a classic logic puzzle trope that improves conditional thinking. Focus: Next in series, analogies, matrix reasoning.
Premise 1: All roses are flowers. Premise 2: Some flowers fade quickly. Conclusion: Some roses fade quickly. Question: Is this conclusion necessarily true? (Answer: No – the roses might be in the subset of flowers that do not fade quickly.)