It affects, in the first place, the nature of logic itself. If thought or intelligence is the means of intentional reconstruction of experience, then logic, as an account of the procedure of thought, is not purely formal. It is not confined to laws of formally correct reasoning apart from truth of subject-matter. Neither, on the contrary, is it concerned with the inherent thought structures of the universe, as Hegel's logic would have it; nor with the successive approaches of human thought to this objective thought structure as the logic of Lotze, Bosanquet, and other epistemological logicians would have it. If thinking is the way in which deliberate reorganization of experience is secured, then logic is such a clarified and systematized formulation of the procedures of thinking as will enable the desired reconstruction to go on more economically and efficiently. In language familiar to students, logic is both a science and an art; a science so far as it gives an organized and tested descriptive account of the way in which thought actually goes on; an art, so far as on the basis of this description it projects methods by which future thinking shall take advantage of the operations that lead to success and avoid those which result in failure. Thus is answered the dispute whether logic is empirical or normative, psychological or regulative. It is both. Logic is based on a definite and executive supply of empirical material. Men have been thinking for ages. They have observed, inferred, and reasoned in all sorts of ways and to all kinds of results. Anthropology, the study of the origin of myth, legend and cult; linguistics and grammar; rhetoric and former logical compositions all tell us how men have thought and what have been the purposes and consequences of different kinds of thinking. Psychology, experimental and pathological, makes important contributions to our knowledge of how thinking goes on and to what effect. Especially does the record of the growth of the various sciences afford instruction in those concrete ways of inquiry and testing which have led men astray and which have proved efficacious. Each science from mathematics to history exhibits typical fallacious methods and typical efficacious methods in special subject-matters. Logical theory has thus a large, almost inexhaustible field of empirical study.