A borrowed ring is locked on a 4 digit combination brass lock and, the dials are mixed. Spectator can test that the lock cannot be opened.
Spectator thinks of any 4 digit number dials them on the lock.This proves to be the secret numbers that opens the lock! No forceof any
pre-conditioned numbers such as someone's year of birth, anniversary or birthday. You can do either of the following:
1. Ask spectator to name ANY 4 digit number
2. Project the 4 digit number to their mind and have the spectator name it.
3. Have 4 different people name a single number each to form the 4 digit number.

Whatever numbers the spectators have chosen, they put the numbers and open the lock with their own hands!