An extract from Sapiens by Yuval Noah Harari.

In the months leading up to their moon voyage expedition, the Apollo 11 astronauts trained in a remote moon-like desert in the western United States. The area is home to several Native American communities, and there is a story – or legend – describing an encounter between the astronauts and one of the locals. One day as they were training, the astronauts came across an old Native American. The man asked them what they were doing there. They replied that they were part of a research expedition that would shortly travel to explore the moon. When the old man heard that, he fell silent for a few moments, and then asked the astronauts if they could do him a favour.

‘What do you want?’ they asked.

‘Well,’ said the old man, ‘the people of my tribe believe that holy spirits live on the moon. I was wondering if you could pass an important message to them from my people.’

‘What’s the message?’ asked the astronauts.

The man uttered something in his tribal language, and then asked the astronauts to repeat it again and again until they had memorised it correctly.

‘What does it mean?’ asked the astronauts.

‘Oh, I cannot tell you. It’s a secret that only our tribe and the moon spirits are allowed to know.’

When they returned to their base, the astronauts searched and searched until they found someone who could speak the tribal language, and asked him to translate the secret message.

When they repeated what they had memorized, the translator started to laugh uproariously. When he calmed down, the astronauts asked him what it meant. The man explained that the sentence they had memorized so carefully said,