The Critique of Pure Reason is more obscure and difficult than even a metaphysical treatise has any right to be. The difficulties are not merely due to defects of exposition; they multiply rather than diminish upon detailed study; and, as I shall endeavour to show in this Commentary, are traceable to two main causes, the composite nature of the text, written at various dates throughout the period 1772-1780, and the conflicting tendencies of Kant’s own thinking.

The Commentary is both expository and critical; and in exposition no less than in criticism I have sought to subordinate the treatment of textual questions and of minor issues to the systematic discussion of the central problems. Full use is made of the various selections from Kant’s private papers that have appeared, at intervals, since the publication of his Lectures on Metaphysics in 1821. Their significance has not hitherto been generally recognised in English books upon Kant. They seem to me to be of capital importance for the right understanding of the Critique.

Some apology is perhaps required for publishing a work of this character at the present moment. It was completed, and arrangements made for its publication, shortly before the outbreak of war. The printers have, I understand, found in it a useful stop-gap to occupy them in the intervals of more pressing work; and now that the type must be released, I trust that in spite of, or even because of, the overwhelming preoccupations of the war, there may be some few readers to whom the volume may be not unwelcome. That even amidst the distractions of actual campaigning metaphysical speculation can serve as a refuge and a solace is shown by the memorable example of General Smuts. He has himself told us that on his raid into Cape Colony in the South African War he carried with him for evening reading the Critique of Pure Reason. Is it surprising that our British generals, pitted against so unconventional an opponent, should have been worsted in the battle of wits?

The Critique of Pure Reason is a philosophical classic that marks a turning-point in the history of philosophy, and no interpretation, even though now attempted after the lapse of a hundred years, can hope to be adequate or final. Some things are clearer to us than they were to Kant’s contemporaries; in other essential ways our point of view has receded from his, and the historical record, that should determine our judgments, is far from complete. But there is a further difficulty of an even more serious character. The Critique deals with issues that are still controversial, and their interpretation is possible only from a definite standpoint. The limitations of this standpoint and of the philosophical milieu in which it has been acquired unavoidably intervene to distort or obscure our apprehension of the text. Arbitrary and merely personal judgments I have, however, endeavoured to avoid. My sole aim has been to reach, as far as may prove feasible, an unbiassed understanding of Kant’s great work.

Among German commentators I owe most to Vaihinger, Adickes, B. Erdmann, Cohen, and Riehl, especially to the first named. The chief English writers upon Kant are Green, Caird, and Adamson. In so far as Green and Caird treat the Critical philosophy as a half-way stage to the Hegelian standpoint I find myself frequently in disagreement with them; but my indebtedness to their writings is much greater than my occasional criticisms of their views may seem to imply. With Robert Adamson I enjoyed the privilege of personal discussions at a time when his earlier view of Kant’s teaching was undergoing revision in a more radical manner than is apparent even in his posthumously published University lectures. To the stimulus of his suggestions the writing of this Commentary is largely due.

My first study of the Critique was under the genial and inspiring guidance of Sir Henry Jones. With characteristic kindliness he has read through my manuscript and has disclosed to me many defects of exposition and argument. The same service has been rendered me by Professor G. Dawes Hicks, whose criticisms have been very valuable, particularly since they come from a student of Kant who on many fundamental points takes an opposite view from my own.

I have also to thank my colleague, Professor Oswald Veblen, for much helpful discussion of Kant’s doctrines of space and time, and of mathematical reasoning.

Mr. H. H. Joachim has read the entire proofs, and I have made frequent modifications to meet his very searching criticisms. I have also gratefully adopted his revisions of my translations from the Critique. Similar acknowledgments are due to my colleague, Professor A. A. Bowman, and to my friend Dr. C. W. Hendel.

I have in preparation a translation of the Critique of Pure Reason, and am responsible for the translations of all passages given in the present work. In quoting from Kant’s other writings, I have made use of the renderings of Abbott, Bernard, and Mahaffy; but have occasionally allowed myself the liberty of introducing alterations.

Should readers who are already well acquainted with the Critique desire to use my Commentary for its systematic discussions of Kant’s teaching, rather than as an accompaniment to their study of the text, I may refer them to those sections which receive italicised headings in the table of contents.

NORMAN KEMP SMITH.

London, January 1918.