As an illustration of impure agnosticism take Hume’s a priori argument against miracles, leading on to the analogous case of the attitude of scientific men towards modern spiritualism.  Notwithstanding that they have the close analogy of mesmerism as an object-lesson to warn them, scientific men as a class are here quite as dogmatic as the straightest sect of theologians.  I may give examples which can cause no offence, inasmuch as the men in question have themselves made the facts public, viz. ——­ refusing to go to [a famous spiritualist]; ——­ refusing to try ——­ in thought-reading[42].  These men all professed to be agnostics at the very time when thus so egregiously violating their philosophy by their conduct.

Of course I do not mean to say that, even to a pure agnostic, reason should not be guided in part by antecedent presumption—­e.g. in ordinary life, the prima facie case, motive, &c., counts for evidence in a court of law—­and where there is a strong antecedent improbability a proportionately greater weight of evidence a posteriori is needed to counterbalance it:  so that, e.g. better evidence would be needed to convict the Archbishop of Canterbury than a vagabond of pocket-picking.  And so it is with speculative philosophy.  But in both cases our only guide is known analogy; therefore, the further we are removed from possible experience—­i.e. the more remote from experience the sphere contemplated—­the less value attaches to antecedent presumptions[43]. Maximum remoteness from possible experience is reached in the sphere of the final mystery of things with which religion has to do; so that here all presumption has faded away into a vanishing point, and pure agnosticism is our only rational attitude.  In other words, here we should all alike be pure agnostics as far as reason is concerned; and, if any of us are to attain to any information, it can only be by means of some super-added faculty of our minds.  The questions as to whether there are any such super-added faculties; if so, whether they ever appear to have been acted upon from without; if they have, in what manner they have; what is their report; how far they are trustworthy in that report, and so on—­these are the questions with which this treatise is to be mainly concerned.

My own attitude may be here stated.  I do not claim any [religious] certainty of an intuitive kind myself; but am nevertheless able to investigate the abstract logic of the matter.  And, although this may seem but barren dialectic, it may, I hope, be of practical service if it secures a fair hearing to the reports given by the vast majority of mankind who unquestionably believe them to emanate from some such super-added faculties—­numerous and diverse though their religions be.  Besides, in my youth I published an essay (the Candid Examination) which excited a good deal of interest at the time, and has been long out of print.  In that treatise