The back of the box is not advertising — it is a legal document, and it has to tell you the truth. The front of the box is advertising, and some of its favourite words mean nothing at all.

Researchers asked students how long their big project would take, then asked for a worst-case guess too. The real answer came in later than the worst case. There is a name for this, and once you know it you can plan around it.

Read it again. Then again. It all looks familiar, so you must know it — and that feeling is the single most reliable way to walk into an exam having learned almost nothing. Researchers have been measuring this since 1885.

There is a method for finding what broke, and the strange thing about it is that it never needs you to understand the thing you are fixing. Five checks will find one dead bulb in a string of thirty-two. Doubling the string costs you one more check.

Researchers gave the same website to professional fact-checkers, to historians with doctorates, and to Stanford undergraduates. The fact-checkers were faster and more accurate — and the first thing they did was leave the page.

Hearing a statement a second time makes people rate it as more likely to be true. It has been reproduced for nearly fifty years, and the unsettling part is that it still works on people who can tell you the correct answer.

Your shoe is missing. You have looked everywhere and it is not anywhere. There is a way to look that works better than looking everywhere, and the strangest step is the last one.