Meanwhile the first thing that anyone learns who attends seriously to these phenomena is that their causation is far too complex for our feelings about what is or is not romantic enough to be spiritual to throw any light upon it. The causal factors must be carefully distinguished and traced through series, from their simplest to their strongest forms, before we can begin to understand the various resultants in which they issue. Myers and Gurney began this work, the one by his serial study of the various sorts of "automatism," sensory and motor, the other by his experimental proofs that a split-off consciousness may abide after a post-hypnotic suggestion has been given. Here we have subjective factors; but are not transsubjective or objective forces also at work? Veridical messages, apparitions, movements without contact, seem _prima facie_ to be such. It was a good stroke on Gurney's part to construct a theory of apparitions which brought the subjective and the objective factors into harmonious co-operation. I doubt whether this telepathic theory of Gurney's will hold along the whole line of apparitions to which he applied it, but it is unquestionable that some theory of that mixed type is required for the explanation of all mediumistic phenomena; and that when all the psychological factors and elements involved have been told off--and they are many--the question still forces itself upon us: Are these all, or are there indications of any residual forces acting on the subject from beyond, or of any "meta-psychic" faculty (to use Richet's useful term) exerted by him? This is the problem that requires real expertness, and this is where the simple sentimentalisms of the spiritist and scientist leave us in the lurch completely.