Enigma Solitario

The Solitaire Mystery (Norwegian: Kabalmysteriet) is a 1990 fantasy novel by Jostein Gaarder, the Norwegian author of the best-selling Sophie's World. Its main target audience is young adults, but the themes of the book transcend any age group. The Solitaire Mystery, as with Sophie's World, has a philosophical content but, unlike Sophie's World, it does not explicitly mention philosophers and theories; thus readers of the book may be unaware that they are actually engaging in philosophy.