The magician approaches a passer-by and asks that they hold a pack of cards and to merely think of any card that is in the pack.
"Are you thinking of one ?" - "Not the Ace of Spades ! " - "Think of another ."
"OK - got one ? - Yes ? - OK, I want you to visualise your card turning around, can you do that ?"
"What's the name of your card ?"
The spectators announces his 'Thought card' - "The 5 of Diamonds".