"No; personally I do not entertain that theory for a moment. But I am considering the evidence apart from our opinions on the subject. We have to accept it as a conceivable hypothesis that it may be sleeping sickness because we cannot positively prove that it is not. That is all. But when we come to the hypothesis of morphine poisoning, the case is different. The symptoms agree with those of morphine poisoning in every respect. There is no exception or disagreement whatever. The common sense of the matter is therefore that we adopt morphine poisoning as our working diagnosis; which is what you seem to have done." "Yes. For purposes of treatment." "Exactly. For medical purposes you adopted the more probable view and dismissed the less probable. That was the reasonable thing to do. But for legal purposes you must entertain both possibilities; for the hypothesis of poisoning involves serious legal issues, whereas the hypothesis of disease involves no legal issues at all." "That doesn't sound very helpful," I remarked. "It indicates the necessity for caution," he retorted. "Yes, I see that. But what is your own opinion of the case?" "Well," he said, "let us consider the facts in order. Here is a man who, we assume, is under the influence of a poisonous dose of morphine. The question is, did he take that dose himself or was it administered to him by some other person? If he took it himself, with what object did he take it? The history that was given to you seems completely to exclude the idea of suicide. But the patient's condition seems equally to exclude the idea of morphinomania. Your opium-eater does not reduce himself to a state of coma. He usually keeps well within the limits of the tolerance that has been established. The conclusion that emerges is, I think, that the drug was administered by some other person; and the most likely person seems to be Mr. Weiss." "Isn't morphine a very unusual poison?" "Very; and most inconvenient except in a single, fatal dose, by reason of the rapidity with which tolerance of the drug is established. But we must not forget that slow morphine poisoning might be eminently suitable in certain cases. The manner in which it enfeebles the will, confuses the judgment and debilitates the body might make it very useful to a poisoner whose aim was to get some instrument or document executed, such as a will, deed or assignment. And death could be produced afterwards by other means. You see the important bearing of this?" "You mean in respect of a death certificate?"