IV. The critical process comprises two series of questions, which correspond to the two series of operations by which the document was produced. All that interpretative criticism tells us is what the author meant; it remains to determine (1) what he really believed, for he may not have been sincere; (2) what he really knew, for he may have been mistaken. We may therefore distinguish a _critical examination of the author's good faith_, by which we seek to determine whether the author of the document lied or not, and a _critical examination_ of his _accuracy_, by which we seek to determine whether he was or was not mistaken. In practice we rarely need to know what an author believed, unless we are making a special study of his character. We have no direct interest in the author; he is merely the medium through which we reach the external facts he reports. The aim of criticism is to determine whether the author has reported the facts correctly. If he has given inexact information, it is indifferent whether he did so intentionally or not; to draw a distinction would complicate matters unnecessarily. There is thus little occasion to make a separate examination of an author's good faith, and we may shorten our labours by including in a single set of questions all the causes which lead to misstatement. But for the sake of clearness it will be well to discuss the questions to be asked in two separate series. The questions in the first series will help us to inquire whether we have any reason to distrust the sincerity of a statement. We ask whether the author was in any of those situations which normally incline a man to be insincere. We must ask what these situations are, both as affecting the general composition of a document, and as affecting each particular statement. Experience supplies the answer. Every violation of truth, small or great, is due to a wish on the part of the author to produce a particular impression upon the reader. Our set of questions thus reduces to a list of the motives which may, in the general case, lead an author to violate truth. The following are the most important cases:--