The External Witness

This site checks itself. Every claim it publishes re-derives in continuous integration and again in your browser while you read. It still cannot call any of it published, because the rule it wrote for itself requires one thing a machine cannot generate: somebody outside it who saw the thing with their own eyes.

Ten chapters, each on a real page of this site. You will not be quizzed on anything the page does not show you, and three of the chapters cannot be signed by reading at all: you have to use the instrument. A bar follows you while the case is open and gets out of the way when it is not.