The controversy between teleologists and deontologists, whether under these names or in other guises, is one of the long-standing disputes of ethics. In different branches of philosophy the perennial nature of a dispute may point to different things: in some, for example, it may properly incline one to say “a plague on both your houses” and thereafter to look for some way of disposing of the whole problem around which the philosophical problem has raged; in ethics, on the other hand, root-and-branch methods of excision are to be deplored, for here a perennial issue usually draws attention to points of view which have somehow to be reconciled if the problems underlying them are to be overcome. The deontology-teleology controversy seems to me a case in point. Here, if anywhere in ethics, a reconciliation must be effected; and in the present paper my primary aim is to induce deontologists and teleologists to abandon their mutual hostility.1I shall attempt to carry out this mission of philosophical good will through examining the ways in which we justify imperatives. In the first section of the paper I shall say something about the controversy itself, making it clear that I consider that it has roots which it would be inconvenient to expose at this stage of the inquiry; in the second I shall study the justification of a number of typical non-moral imperatives; in the third I shall apply the findings of the second to the justification of moral imperatives; and finally, in the fourth section I shall return to the deontology-teleology controversy and attempt to elucidate how it arises, to point out the two levels on which the same dispute (as it seems to me) can be found, and to suggest a way in which the essentials of the rival views may be accepted and combined.

“The composition of the lectures of which Aristotle's extant works are the notes probably belongs in the main to the twelve or thirteen years of tail headship of the Lyceum, and the thought and research implied, even if we suppose that some of the spadework was done for him by pupils, implies an energy of mind which is perhaps unparalleled. During this time Aristotle fixed the main outlines of the classification of the sciences in the form which they still retain, and carried most of the sciences to a further point than they had hitherto reached; in some of them, such as logic, he may fairly claim to have had no predecessor, and for centuries no worthy successor…one of the greatest of analytic thinkers. “SIR W. DAVID ROSS, Aristotle.

Operative Logic and Mathematics would appear to be a new venture. Only a few weeks before his premature death Hermann Weyl, one of the most original mathematicians of our time, the author of a Philosophy of Mathematics and Natural Science and also of a stimulating book on Symmetry, drew my attention to Paul Lorenzen's Einführung in die operative Logik und Mathematik(Springer, Berlin). This book had given him new hope, since GÖdel had discouraged his endeavour to find the foundations of mathematics. “Perhaps,” he added, “Lorenzen's approach promises a way of arriving at reliable foundations.”

This question as to whether machines can, or could, be made to think, has become familiar in recent years since the renewed outburst of interest that has taken place in the development of Cybernetics. The notion of servo–mechanisms and the like has a history in remote antiquity but the form of its fundamental question has recently taken on a new and especially acute significance.