to be confined to mere presumption and counter-presumption, with no decisive thunderbolt of fact to clear the baffling darkness. And, sooth to say, in talking so much of the merely presumption-weakening value of our records, I have myself been wilfully taking the point of view of the so-called 'rigorously scientific' disbeliever, and making an ad hominem plea. My own point of view is different. For me the thunderbolt has fallen, and the orthodox belief has not merely had its presumption weakened, but the truth itself of the belief is decisively overthrown. If I may employ the language of the professional logic-shop, a universal proposition can be made untrue by a particular instance. If you wish to upset the law that all crows are black, you must not seek to show that no crows are; it is enough if you prove one single crow to be white. My own white crow is Mrs. Piper. In the trances of this medium, I cannot resist the conviction that knowledge appears which she has never gained by the ordinary waking use of her eyes and ears and wits. What the source of this knowledge may be I know not, and have not the glimmer of an explanatory suggestion to make; but from admitting the fact of such knowledge I can see no escape. So when I turn to the rest of the evidence, ghosts and all, I cannot carry with me the irreversibly negative bias of the 'rigorously scientific' mind, with its presumption as to what the true order of nature ought to be. I feel as if, though the evidence be flimsy in spots, it may nevertheless collectively carry heavy weight. The rigorously scientific mind may, in truth, easily overshoot the mark. Science means, first of all, a certain dispassionate method. To suppose that it means a certain set of
