alternatives. M-deception reduces the ambiguity in the victim's mind by having him become convinced of a particular falsehood. (Either form of deception can be accomplished, incidentally, by telling only the truth — as Lewin (9) quoted one of the "A" Force deception experts, "truths do not constitute the truth.")
A-deception can function by altering the probabilities attached to various outcomes in the mind of the opponent, diluting or burying useful information in noise and/or by altering the perceived range of options and outcomes available to the opponent. Roberta Wohlstetter's (5) classic analysis of the Pearl Harbor surprise borrowed the concepts of signal and noise from communications theory. Her dictum, "to understand the fact of surprise it is necessary to examine the characteristics of the noise as well as the signals that after the event, are clearly seen to herald the attack," has a corollary to the effect that noise can be created by the deception architect to overpower or swamp the signal. Jervis (37) also remarks on the advantages of ambiguity in international relations. Eric Ambler, in a recent novel entitled, "Send No More Roses," (38) stated the principle of A-deception elegantly and simply by having one of the story's protagonists muse: we gave
