Spot the hidden assumption

What you’ll do in this quiz

Hidden assumptions are the quiet “of course” statements that an argument depends on, even when they’re never said out loud. This quiz trains you to notice what must be true for a conclusion to follow.

Each question is multiple-choice with 4 options and no timer, so you can slow down and test each option against the claim. You can also choose your question count and difficulty before you start, making it easy to do a quick warm-up or a longer mixed session.

Skills you’ll practice

You’ll get better at separating evidence from conclusions and spotting gaps that are covered by an unstated premise. Over time, you’ll recognize common reasoning patterns—like causal leaps, overgeneralizations, and “either/or” framing.

Common pitfalls to avoid

Many wrong answers sound reasonable but aren’t required by the argument. Watch out for options that add new facts, strengthen the conclusion more than necessary, or introduce a different topic than the original claim.

How the difficulty stays balanced

Because the difficulty is Mixed, you’ll see a blend of straightforward assumptions and more subtle ones that rely on careful wording. Easier items focus on one clear missing link, while harder ones include tempting distractors that are plausible but not essential.

• Identify the conclusion first, then ask: “What must be true for this to hold?”
• Prefer the option that is necessary, not merely helpful or likely
• Be cautious with extreme words (always, never) unless the argument demands them
• Don’t pick background facts that aren’t required for the reasoning to work
• If two options seem close, test which one the argument collapses without