Aristotle, the Fallacy of Accident, and the Nature of Predication: A Historical Inquiry

Aristotle, the Fallacy of Accident, and the Nature of Predication: A Historical Inquiry AN|BAL A. BUENO 1. In the analysis of informal fallacies in English-language logical treatises we usually find one called the fallacy of accident and another that is characterized as its converse. The latter is also usually called the fallacy a dicto secundum quid ad dictum simpliciter, or simply secundum quid. Accident is usually defined as the application of a general rule to a case in which, because of some accidental feature it possesses, the rule does not apply. Sometimes the fallacy is defined in more traditional language as inferring of a subject with an accident that which is known to be the case of the subject only. The converse fallacy is defined as generalizing from an atypical or abnormal instance, or inferring of a subject that which is true of the subject with an accident. This fallacy is sometimes called hasty generalization. ~ The preceding definitions of these fallacies lead to serious difficulties which have been analyzed by some theorists, but their objections have not yet led to a general reassessment of them. 2The main criticisms are the following. ' See Irving Copi, Introduction to Logic, 6th ed. (NewYork: Macmillan, 1982), lO6-7; Henry Byerly,A Primer ofLogic (Harper and Row, 1973),47-48; John Grier Higben, Logic. Deductive and Inductive (NewYork: Scribners, x912), 161; W. StanleyJevons, Elementary Lessons in Logic: Deductive andlnductive (NewYork and London: 19o4), 176-78. ' A discussion of these difficulties maybe found in Aristotle on Fallacies or The Sophistici Elenchi, trans, and ed. Edward Poste (London, 1866), 158. See also H. W. B. Joseph, An Introduction to Logic (Oxford, 19o6,2d ed. 1916;reprint 1931),587-88. C. L. Hamblin, Fallacies (London: x97o), 25-31 . [5] 6 JOURNAL OF THE HISTORY OF PHILOSOPHY 26:i JANUARY i988 1. There are many arguments about which we cannot tell whether the inference moves from a particular or restricted case to a more general case, or vice versa. Let us consider an example:3 A person who thrusts a knife into another person's body is guilty of a crime and should be punished. Surgeons thrust knives into other people's bodies. Therefore, surgeons are criminals and should be punished. This argument may be interpreted in two ways. We can consider the first premiss as a general rule (namely thrusting a knife without any further qualification ) and the second as a more restricted case (thrusting a knife with the intention of curing). Under this interpretation, the inference moves from a broader to a more restricted case, and the argument is a case of the fallacy of accident. But we can also interpret the first premiss as a qualified statement that refers to thrusting a knife with the intention of harming a person, and the second as the general case of thrusting a knife without any further qualification . Now the movement of meaning is reversed, and the argument becomes a case of secundum quid. In view of the fact that many arguments can be construed as one or the other fallacy, the distinction seems artificial. That it is difficult to distinguish between the two fallacies is clearly shown by the fact that a classical example of secundum quid: What you buy at the market today, you will eat tomorrow. You bought raw meat at the market today. Therefore, you will eat raw meat tomorrow. This is cited by I. Copi and by M. R. Cohen and E. Nagel in their well-known logic books as an instance of accident.4 Augustus De Morgan remarked that "this piece of meat has remained uncooked, fresh as ever, a prodigious time."5 The meat may still be fresh, but the fallacy has changed. In fact, many arguments move neither from a general to a restricted case, nor in the opposite direction, but from one special case to another. For this reason both De Morgan and W. S. Jevons proposed a third type of fallacy, namely "arguing from one special case to another special case," or a dicto secundum quid ad dictum secundum alterum quid, but this suggestion has found no acceptance. 6 3 I have borrowed this example and the...