Ambiguity Fallacy

(also known as: amphiboly, semantical ambiguity, type-token ambiguity [form of], vagueness)

Description: When an unclear phrase with multiple definitions is used within the argument; therefore, does not support the conclusion.  Some will say single words count for the ambiguity fallacy, which is really a specific form of a fallacy known as equivocation.

Logical Form:

Claim X is made.

Y is concluded based on an ambiguous understanding of X.

Example #1:

It is said that we have a good understanding of our universe.  Therefore, we know exactly how it began and exactly when.

Explanation: The ambiguity here is what exactly “good understanding” means.  The conclusion assumes a much better understanding than is suggested in the premise; therefore, we have the ambiguity fallacy.

Example #2:

All living beings come from other living beings.  Therefore, the first forms of life must have come from a living being.  That living being is God.

Explanation: This argument is guilty of two cases of ambiguity.  First, the first use of the phrase, “come from”, refers to reproduction, whereas the second use refers to origin.  The fact that we know quite a bit about reproduction is irrelevant when considering origin.  Second, the first use of, “living being”, refers to an empirically verifiable, biological, living organism.  The second use of, “living being”, refers to a belief of an immaterial god.  As you can see, when a term such as, “living being”, describes a Dodo bird as well as the all-powerful master of the universe, it has very little meaning and certainly is not specific enough to draw logical or reasonable conclusions.

Exception: Ambiguous phrases are extremely common in the English language and are a necessary part of informal logic and reasoning.  As long as these ambiguous phrases mean exactly the same thing in all uses of phrase in the argument, this fallacy is  not committed.

Variation: The type-token fallacy is committed when a word can refer to either a type (cars) or token (Prius, RAV4, Camry) is used in a way that makes it unclear which it refers to, the statement is ambiguous.

Toyota manufactures dozens of cars.

This obviously refers to the different types of cars, not how many instances (or tokens) of each car were manufactured.


+3 #1 ThatGirlDoingHomwork 2012-09-26 20:02
:sigh: :o What?!
0 #2 Seth 2014-01-22 07:37
'As you can see, when a term such as, “living being”, describes a do-do bird as well as the all-powerful master of the universe, it has very little meaning ...'

It has very little meaning because it has way too much meaning. right?
+2 #3 Bo Bennett 2014-01-22 07:38
That which describes everything, describes nothing.
-1 #4 Seth 2014-01-22 08:15
i didnt really understand what you meant by a token

Because first it appears to be alluding to a model of something (rav4, prius) then u've used it in a different way by saying that an instance is a token
0 #5 Bo Bennett 2014-01-22 17:22
The word "dozen" is simply ambiguous. It is neither a type nor token, but refers to the token not the type. Clear? :eek:
+1 #6 Rossally 2014-02-04 14:08
I love how you labeled some of Thomas Aquinas' reasoning as a logical fallacy. Philosophy in the Middle Ages was pretty fallacious indeed. Haha.

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