What is the key to hypnosis?
There is more than 1 key. There are a few.
It depends on what type of hypnosis we are talking about:
In hypnotherapy session, Relaxation is the key.
In stage hypnosis, the physical parts of our body is the key eg the eyes and the head.
In street hypnosis, subconscious related words is the key.
In self-hypnosis, Relaxation enhanced by music is the key.