Estabrook implies that hypnotism is possible against the will of the subject. Is this so? And can everyone be hypnotised, or are some people naturally immune!? Does anti-hypnotism always have to be learned? People generally are very easy to persuade --- we only have to look at the numbers who fall for the latest scams--- but I thought hypnotism, as opposed to propaganda-type behaviour modification, had to have consent to be successful.

PS. Obviously I am not talking about drug use in conjunction with hypnosis here.