Читать книгу Best Friends Forever: A gripping psychological thriller that will have you hooked in 2018 - Margot Hunt - Страница 9

Imagine you’re shipwrecked on an island inhabited by only Knights and Knaves. Knights always tell the truth. Knaves always lie. There is no way to distinguish between the two just by looking at them. The only way to separate the liars from the truth-tellers is by asking them questions.

For example, suppose you encounter two islanders. Let’s call them A and B. You ask A, “Are you a Knight or a Knave?”

A responds by saying, “At least one of us is a Knave.”

B is silent.

Who is a Knight and who is a Knave?

The answer is easy. A cannot be a Knave, because if so, his statement would be truthful, and Knaves always lie. Therefore A must be a Knight, and telling the truth. Which would mean B is a Knave.

In real life, of course, there are no such things as Knights, those absolute keepers of the truth.

Everyone lies about something.