The doctor in charge took them all into a room and with a ball pen drew a door on the wall.He then asked each one of his patients to try and open the door for him as part of the test.
Seven of them rushed out and attempted to open the door on the wall.
The doctor was disappointed with the results but never the less, called on, with some hope, to the last one.
He asked him, “Why didn’t you try to open the doors with others.”
The patient smiled wisely and said, “Because I am holding the key to the door!”