Logical Fallacy of Ambiguous Assertion

Ambiguous assertion is one of the many smokescreens that are used to cover the fact that the reasoning is based on one of the three fallacies of Agrippa's trilemma. Whenever a logical fallacy is committed, the fallacy has its roots in Agrippa's trilemma. All human thought (without Divine revelation) is based on one of three unhappy possibilities. These three possibilities are infinite regress, circular reasoning, or axiomatic thinking. This problem is known as Agrippa's trilemma. Some have claimed that only logic and math can be known without Divine revelation; however, that is not true. There is no reason to trust either logic or math without Divine revelation. Science is also limited to the pragmatic because of the weakness on human reasoning, which is known as Agrippa's trilemma.

The Logical Fallacy of Ambiguous Assertion occurs when claims are sufficiently vague as to allow more than one interpretation. Sometimes, statements are so vague the audience is forced to guess what was meant. As with all fallacies, this may be a calculated technique or an error in communication, but the result is that some people may be influenced to believe something that isn’t true.

Examples of the Logical Fallacy of Ambiguous Assertion

Bill Nye arguing against Creation science: ". . . where the fossils of one type of animal cross over into the fossils of another. In other words, when there is a big flood on the Earth, you would expect drowning animals to swim up to a higher level."

The vagueness of this statement, “not a single place in the Grand Canyon where the fossils of one type of animal cross over into the fossils of another,” makes it difficult to answer. Bill is using innuendo rather that stating things clearly. This results in a fallacy of ambiguity. Innuendo is often used as a hedging tactic by people who don't have a real reason to believe what they believe. What is meant by “fossils of one type of animal cross over into the fossils of another”?

There is a lot of mixing of fossils. Is Bill just plain lying? If you were to ask, he could easily modify or redefine his terms in such a way that they would not be a lie--but the statement would then make no point at all.