LOGIC, various definitions have been given of logic, some including too little. and others too much. Logic has been called the Art of Reasoning; this defini tion has been properly amended by call ing it the Seienc,e as well as the Art of Reasoning: meaning by the former, the analysis of the mental process which takes place we reason ; and, by the latter, the rules grounded upon that analysis for conducting the process cor rectly. But the word Reasoning, again, is ambiguously used. In one of its ac ceptations it means syllogizing, or that mode of inference which may he called concluding from generals to particulars. The better definition of this term, how ever, and that which aceords more with the general usage of the English lan guage. makes it signify the inferring of any assertion from assertions already ad mitted. But the province of logic is wider than reasoning even in this exten sive sense, for it undoubtedly includes, for instance, precision of language and accuracy of classification ; in other words, definition and division. These various operations might be brought within the compass of the science, by defining logic as the science which treats of the opera tions of the human tunlerstanding in the pursuit of truth. 'Phis definition, how ever, includes too much. Truths are known to us in two ways : some are known directly and of themselve:+; some through the medium of other truths. It is only with the latter that logic has to do. Logic is not the science of belief, hut the science of proof. lint as the far greatest portion of our knowledge, whether of general truths, or of particular facts, is avowedly matter of inference, our defini tion of logic is in danger of including the whole field of knowledge; unless wo qualify it by some further limitation, showing where the domain of the .dhor
arts and sciences, and of common pru dence ends, and that of logic begins. The distinction is, that the science or knowl edge of the particular subject in:titer furnishes the evidence, while logic fur nishes the principles and rules of the esti mation of evidence : logic points out what relations must subsist between data, and whatever can be concluded from them. " Logic, then, is the science of the opera tions of the understanding which are sub servient to the estimation of evidence : both the process itself of proceeding from known truths to unknown, and all intel lectual operations auxiliary to this." Logic was highly valued, perhaps over eatned, among the ancient philosophers. The Stoics in particular were celebrated for their application of its principles to their own favorite metaphysical discus sions. From the abuse of 1%gical knowl edge arose the celebrated fallacies of the Sophists. Zeno is called the father of logic or dialectics; but it was then treated with particular reference to the art of disputation, and soon degenerated into the minister of sophistry. It is to Aris totle, however, that the science owes, not only its first exposition, but its complete development. Ills writings were called Organan in later ages, and for almost two thousand years after him maintained authority in the schools of the philosophers, and in the middle ages it became the foundation of the scholas tic philosophy, which was little better than a revival under another form, of the logic of the Athenian Sophists.