- fidently meet them on the field which they themselves have
chosen.
First, then, it is at least a rather startling supposition that their fellow creatures have always been, and are still, the victims of a universal delusion, from which they alone enjoy the privilege of exemption. Presumption, at all events, is against a man who asserts that everybody but himself sees wrongly. He may be the only person whose eyes have not deceived him, but we should require him to give the strongest proof of so extraordinary an assertion. And in all cases which are in the least degree similar, this condition is complied with without the smallest hesitation. There are, so far as I am aware, no instances of proved universal delusions, save those arising from the misleading suggestions of the senses. That the earth is a flat surface, that the sun moves round it, that the sun and moon are larger than the stars, that the blue sky begins at a fixed place, are inferences which the uninstructed observer cannot fail to draw from the most obvious appearances. But those who have combated these errors have not done so by merely telling the world at large that it was mistaken; they have pointed out the phenomena from which the erroneous inferences were drawn, and have shown at the same time that other phenomena, no less evident to the senses than these, were inconsistent with the explanation given. They have then substituted an explanation which accounted for all the phenomena alike, both the more obvious phenomena and the less so. Precisely similar is the method of procedure in history and philosophy, though the methods of proof in these sciences are not equally rigorous. Great historical delusions—such as the Popish plot—are put to rest by showing the misinterpreted facts out of which they have grown, exposing the misinterpretation, and substituting true interpretation. Imperfect psychological analysis, say of an emotion, is superseded by showing from what facts this analysis has been obtained, and what other facts it fails to account for.
Observe, then, that in all these cases the appeal is made from the first impressions of the mistaken person to his own impressions on further examination; not to those of another. Considerations are laid before him which it is supposed will cause
