There is only too much truth in the frequent complaint that history, as compared with the physical sciences, is neglected by the modern public. But historians have the remedy in their own hands; choosing problems of equal importance to those of the scientist, and treating them with equal accuracy, they will command equal attention. Those who insist that the proportion of accurately ascertainable facts is smaller in history, and therefore the room for speculation wider, do not thereby establish any essential distinction between truth-seeking in history and truth-seeking in chemistry. The historian, whatever be his subject, is as definitely bound as the chemist “to proclaim certainties as certain, falsehoods as false, and uncertainties as dubious.” Those are the words, not of a modern scientist, but of the seventeenth century monk, Jean Mabillon; they sum up his literary profession of faith. Men will follow us in history as implicitly as they follow the chemist, if only we will form the chemist’s habit of marking clearly where our facts end and our inferences begin. Then the public, so far from discouraging our speculations, will most heartily encourage them; for the most positive man of science is always grateful to anyone who, by putting forward a working theory, stimulates further discussion.

The present series, therefore, appeals directly to that craving for clearer facts which has been bred in these times of storm and stress. No care can save us altogether from error; but, for our own sake and the public’s, we have elected to adopt a safeguard dictated by ordinary business commonsense. Whatever errors of fact are pointed out by reviewers or correspondents shall be publicly corrected with the least possible delay. After a year of publication, all copies shall be provided with such an erratum-slip without waiting for the chance of a second edition; and each fresh volume in this series shall contain a full list of the errata noted in its immediate predecessor. After the lapse of a year from the first publication of any volume, and at any time during the ensuing twelve months, any possessor of that volume who will send a stamped and addressed envelope to the Cambridge University Press, Fetter Lane, Fleet Street, London, E.C. 4, shall receive, in due course, a free copy of the errata in that volume. Thus, with the help of our critics, we may reasonably hope to put forward these monographs as roughly representing the most accurate information obtainable under present conditions. Our facts being thus secured, the reader will judge our inferences on their own merits; and something will have been done to dissipate that cloud of suspicion which hangs over too many important chapters in the social and religious history of the Middle Ages.

G. G. C.

October, 1922.