Most people know the tarot as fortune-telling. The tradition treats it as something older and more serious: a book of wisdom written in pictures and numbers.

Its heart is the twenty-two great cards, the major arcana. Each has a number, a letter of the Hebrew alphabet and a name. Read in order, they describe the path you are walking in this book.

The first is the Magician: a human being who decides to begin. The second is the Priestess, the inner wisdom that receives. Further along come the Lover, standing between two roads, and the Tame Lion (Strength in other decks), taming what is wild in you. The thirteenth, often called Death, means in the tradition the death of the selves, and rebirth with it. Near the end come Hope (the Star), Twilight (the Moon) and the Radiant Sun of the inner Christ.

You do not need to learn them all to use the idea. Each card names a moment of the path. Seeing which one you stand at can steady you: a trial is a stage, not the end.

The Observatory in this app holds the tradition’s Egyptian Tarot, for those who want to go further.