Logical Fallacy of Denying the Antecedent / Inverse Error / Fallacy of the Inverse / Invalid modus tollens

Denying the antecedent is a formal fallacy that covers up the problem when 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 the denying the antecedent / inverse error / fallacy of the inverse occurs when the inverse is inferred from the original statement.

"If A then B.
Not A.
Therefore, not B." (invalid form--denying the antecedent / inverse error)

Examples of the Logical Fallacy of Denying the Antecedent / Inverse Error / Fallacy of the Inverse / Invalid modus tollens

"If there ever were a catastrophic worldwide flood then we would expect to find remains of Noah's ark.
No ark has been confirmed as found.
Therefore, there never was a catastrophic worldwide flood."

You can't infer/reason the inverse in this way. This is invalid form--denying the antecedent

"If we had found dinosaur fossils and human fossils next to each other, then we would know that they lived together at the same time.
We have not, however, found dinosaur and human fossils together.
Therefore, we know that they didn't live together."

It's not uncommon to hear this very argument, but it is an irrational argument, using invalid form and denying the antecedent.

"If God raised the dead right in front of me right now, then I would know that He exists.
However, God is not raising the dead in front of me right now.
Therefore, I need to act as if God doesn't exist."

If you run into people who are hostile to the good news about Jesus Christ, you are likely to hear this irrational argument against God, using the invalid form of denying the antecedent. Here's another variation on the same logical fallacy:

"If God would speak to me in an audible voice right now, then I would know that He exists.
However, God is not speaking to me in an audible voice right now.
Therefore, God doesn't exist."

The complexity of God’s Way understood in a single diagram

Obey your flesh and descend into darkness

How can we know anything about anything? That’s the real question

Logical Fallacy of Denying the Antecedent / Inverse Error / Fallacy of the Inverse / Invalid modus tollens

Examples of the Logical Fallacy of Denying the Antecedent / Inverse Error / Fallacy of the Inverse / Invalid modus tollens

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