1) A disk with a picture on each side is attached to two pieces of string. When the strings are twirled quickly between the fingers the two pictures appear to blend into one due to the persistence of vision.
The coined name translates roughly as “wonder turner”, from Ancient Greek: θαῦμα “wonder” and τρόπος “turn”.
To me the ego is the habitual and compulsive thought processes that go through everybody’s mind continuously. External things like possessions or memories or failures or successes or achievements. Your personal history.