How this works

This quiz estimates one thing: the point on the timeline of human knowledge at which your command of settled facts begins to thin out. We call that your knowledge frontier, expressed as a year between 500 and the present.

What this measures, and what it does not

It is not an intelligence test, and the result is not a verdict on how clever you are. That distinction is the whole argument of the essay this quiz accompanies. Knowing that the Earth orbits the Sun, or that DNA is a double helix, places you later on the escalator of accumulated knowledge than Ptolemy or Ibn Sina, but it does not make you their intellectual equal.

You were handed those facts; they had to derive their own. The quiz measures inherited breadth, not the power of the mind that holds it.

The question bank

The quiz draws on 197 questions across seven fields: cosmos, life, matter, medicine, mathematics, earth science and technology. Every question is tagged with the year its fact became settled or establishable knowledge, from the Greek measurement of the Earth before 500 to the genome, the Higgs boson and the public arrival of large language models after 2000. Each was written to be accurate and accessible to an educated general reader, then independently fact-checked for the correctness of its answer, the soundness of its wrong options and the defensibility of its date.

How questions are chosen

The test is adaptive. Rather than asking everyone the same fixed list, it estimates your ability as you go and selects each next question to be most informative at your current level: the questions you have roughly an even chance of answering. It runs four passes across the seven fields, 28 questions in total, so every field is sampled while the difficulty tracks you.

How the result is calculated

Each answer updates an estimate of your ability using item response theory, the standard statistical framework behind adaptive examinations. Because the questions are multiple choice, the model includes a guessing allowance, so a lucky guess is worth less than a confident answer. Your ability is estimated by a Bayesian method that produces both a best estimate and an honest measure of its uncertainty.

That ability is mapped to a frontier year, shown on a timeline against four benchmarks: Ibn Sina (around 1020), Leonardo da Vinci (around 1500), Albert Einstein (around 1920) and the average educated person of the year 2000. The shaded band around your result is the confidence range; with 28 questions it is usually a few decades wide, narrower than a single point would honestly let us pretend.

Calibration and the percentile

The difficulty assigned to each question begins as an informed estimate based on its date, then is refined from real responses, using each player’s measured ability to correct for the fact that harder questions are shown to stronger players. The percentile, when shown, compares your frontier year to the distribution of everyone who has played. It appears only once enough people have taken the quiz for the comparison to mean something.

Honest limitations

• It tests recognition, not derivation. Multiple choice rewards recognising the right answer, which is easier than recalling it and far easier than deriving it from first principles. The result reflects what you can recognise as settled fact, not what you could reconstruct or defend.
• The year scale is a designed dial, not a law of nature. The mapping from ability to a calendar year is calibrated to feel meaningful, not derived from a physical constant. It is deliberately demanding at the modern end: reaching the twentieth century, and the year-2000 benchmark, requires near-flawless play.
• The benchmarks are illustrative. The historical figures mark roughly where their century’s frontier of settled knowledge sat in the fields they worked in. They are reference points on a timeline, not a literal claim that you have beaten a genius.
• It is a short test. Twenty-eight questions give a useful estimate with a stated margin, not a definitive measurement. Two careful runs can differ by a few decades, which is why the confidence band is shown.

Privacy

The quiz sets no cookies and collects no personal information. To power the percentile and the difficulty calibration it records only anonymous, aggregate data: which questions were answered correctly and the resulting frontier year. Nothing identifies you, and the quiz works fully even when this is switched off.