Inductive Ambiguities

Fallacies of Ambiguity involve some confusion over meaning. Here is an example of an Inductive Ambiguity:

"The Polish immigrants to whom we administered the Stanford-Benet I.Q. test scored very poorly. We infer that Polish immigrants just aren't very bright."

The inductive argument is a generalization from the sample, "Polish immigrants to whom we administered the Stanford-Benet I.Q. test," to the population "Polish immigrants." Fitting this argument into the model suggested by Peirce, the unstated (minor) premiss is "All Polish immigrants to whom we administered the Stanford-Benet I.Q. test are Polish immigrants," which is trivially true. Strictly speaking, however, we are only in a position to infer that since the members of our sample scored poorly on our test, other members of the population would also score poorly, if given the test. But what does this have to do with "being very bright"? Well, of course, it is supposed to be an intelligence test. In fact, we know that scoring well on the Stanford-Benet I.Q. test actually has more to do with familiarity with symbols and meanings common in American culture than it has to do with intelligence; but, because intelligence isn't a quality that can be directly observed, doing well on the Stanford-Benet I.Q. test is often used as a stand-in for observed intelligence. That is, psychologists often use "doing well on a Stanford-Benet I.Q. test" as an operational substitute for "intelligence." But the two terms do not really mean the same thing.

On the principle that all arguments are valid (for their type), the best way to understand ambiguous arguments is as arguments with four terms in which an unstated premiss asserts a (false) relation between the two meanings of the confused term. We can render the above argument complete (As an Inductive argument it will never be deductively valid!) by adding the premiss "All those who score poorly on the Stanford-Benet I.Q. test are not very bright," a statement which is false, given the usual informal meaning of "bright." A careful technical analysis will show that the false missing premiss, in this case, is a major premiss. Apparently, then, the Inductive Ambiguities can be considered a special group within the Errors in Observation category. However, the error is so distinctive that it makes sense to class them in a group of their own. There is only one fallacy in the Inductive Ambiguities category. It is...

Inappropriate Operational Definition


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