The history of such reappearances—natural history—is meantime a good subject for observation and experiment. Chronicler and critic can always approach experience with a method complementary to the deductive methods pursued in mathematics and logic: instead of developing the import of a definition, he can investigate its origin and describe its relation to other disparate phenomena. The mathematician develops the import of given ideas; the psychologist investigates their origin and describes their relation to the rest of human experience. So the prophet develops the import of his trance, and the theologian the import of the prophecy: which prevents not the historian from coming later and showing the origin, the growth, and the possible function of that maniacal sort of wisdom. True, the theologian commonly dreads a critic more than does the geometer, but this happens only because the theologian has probably not developed the import of his facts with any austerity or clearness, but has distorted that ideal interpretation with all sorts of concessions and side-glances at other tenets to which he is already pledged, so that he justly fears, when his methods are exposed, that the religious heart will be alienated from him and his conclusions be left with no foothold in human nature. If he had not been guilty of such misrepresentation, no history or criticism that reviewed his construction would do anything but recommend it to all those who found in themselves the primary religious facts and religious faculties which that construction had faithfully interpreted in its ideal deductions and extensions. All who perceived the facts would thus learn their import; and theology would reveal to the soul her natural religion, just as Euclid reveals to architects and navigators the structure of natural space, so that they value his demonstrations not only for their hypothetical cogency but for their practical relevance and truth. [Sidenote: Logic dependent on fact for its importance,]