502. LOGIC : OR, THE RIGHT ass OF REASON, little difference in the sense of one of the terms in the two parts of the syllogism wherein it is used. Let us consider the follow ing sophisms 1. " It is a sin to kill a man ; a murderer is a man ; 'there- fore it is a sin to kill a murderer." Here the word kill in the first proposition signifies to kill unjustly, or without law ; in the conclusion it is taken absolutely for putting a man to death in general, and therefore the inference is not good. 2, " What I am, you are not; but I am aman; therefore you are not a man." This is a relative syllogism : but if it be reduced to a regular categorical form, it will appear there is ambiguity in the terms, thus : " What I am, is a man ; you are not what I am ; therefore you are not a man.." Here what I am in the major proposition is taken especially for my nature; 't ut in the minor proposition the same words are taken individually for my person; therefore the inference must be false, for the syl- logism does not take the term, what I am, both times in, the same sense. 3. " He that says you are an animal says true ; but he that says you are a goose, says you are an animal ; therefore he that says you are a goose, says true." In the major proposition the word animal is the predicate of an incidental proposition ; which incidental proposition being affirmative, renders the predicate of it particular, according to Chap. II. Sect. 2. Axiom 3. and con- sequently the word animal there signifies only human animality. In the major proposition the word animal, for the same reason,, signifies the animality of a goose; whereby it becomes an am- biguous term, and unfit to build the conclusion upon. Or if you say, the word animal in the minor, is taken for human animality, then the minor is evidently false. It is from the last general test of syllogisms, that we de- rive the custom of the respondent in answering the arguments of the opponent, which is to distinguish upon the major or minor proposition, and declare which term is used in two senses, and in what sense the proposition may be true, and in what sense it is false. CI(AP. "IV. Some general Rules to direct our Reasoning. MOST of the general and special, directions given to form our judgments aright in the preceding part of Logic might be rehearsed here ; for the judgments which we pass upon things are generally built on some secret reasoning or argument by, which the proposition is supposed to be proved. But there may he yet some farther assistances given to our reasoning powers in their search after truth, and an observation of the following rules will be of great importance for that cad.
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