The appearance of late of so many essays, manuals, and treatises professing to deal with logic and its affiliated topics is quite noteworthy, and is the manifestation of a need that has become, not merely a crying, but an absolutely groaning one. It is scarcely a metaphor to say that to-day the intellectual world is in great travail over its need of an organon. We are crying unto our logical desire from the depths of our souls and waiting for it as they that wait for the morning. This intensity of our want makes us intolerant of the old incompetences and sets us to fault-finding in the hope of better insight when the current obscurities shall have been dissipated. We scan each effort as it appears, and as it discovers no even single clear organic general principle around which the wealth of knowledge now ascertained can set in order we lay it aside with a feeling of being merely tantalised. We cannot but assimilate our condition to that of the Haunted Man in Bret Harte's clever travesty of Dickens: "'Here again?' said the Haunted Man. 'Here again,' assented the phantom, in a low tone. 'Another novel?' 'Another novel.' 'The old story?' 'The old story.' 'It won't do, Charles! It won't do!' and the Haunted Man buried his head in his hands and groaned." When the singular difficulties of the search are considered, all this is, no doubt, void of that sweet reasonableness that should obtain. Still the interests of progress are too supreme to permit any compromise with error or incompetence. So, although the excellent manual under notice makes no pretensions that are unwarrantable, according to the customs usually observed in such cases, it yet affords salient features, apt as texts for a course of comment that applies, not merely to the doctrine and treatment adopted in it but to the doctrine and methods of the accepted logic-books in general. The book is entitled, "The Science of Thought." This exposes an incompetent comprehension of the topic. The Science of Thought should be a mere branch of psychology. In logic, we of course, have an almost prime need of information concerning the anatomy and physiology of thought. But this is not the peculiar motive of logic. The _raison d'être_ of logic is not the _general_ economy of thought, but the phenomena of _untrue_, _incompetent_, or _fallacious_ thought, or, in other words, _erroneous thought_. Did but the mind of man always supply him with true and competent thoughts he would find no need of seeking logical criteria, however much he might be interested in the phenomenology of thought in general.