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 regression, circular reasoning, or axiomatic thinking. This is known as Agrippa's trilemma. Some have claimed that only logic and math can be known; however, that is not true. Without Divine revelation, neither logic nor math can be known. Science is limited only to pragmatic thinking because of the weakness of human reasoning, which is known as Agrippa's trilemma. Presumption, a form of axiomatic thinking, is one of these three unhappy possibilities.

Fallacies of presumption occur when someone simply presupposes or presumes evidence that doesn’t exist or isn’t shown. Premises or conclusions are put forward based on presumption/presupposition.

Example of the Logical Fallacy of Presumption

Sandy: "Roxanne is a fundamentalist Christian. She says man was created 6 days after the universe was. There is absolutely no evidence for this; rather there is a plethora of evidence for evolution which Roxanne chooses to ignore. (Roxanne probably uses logical fallacies to ignore said things.) In light of this, Roxanne is being a moronic fundamentalist Christian."

Roxanne: "The ad hominem attack doesn’t hide the fact that you have shown no support for your assertions. First, there absolute evidence that God created the Heavens and the Earth in just six days. God is saying that He did. Revelation proves it. Every other story rests on assumptions and made-up stories, as opposed to revelation. If there were a plethora of real evidence that would prove beyond a shadow of a doubt that evolution actually happened, you could show it. To my knowledge there is no evidence that molecules actually made the step-by-step progress to become increasingly complex forms of life until humanity came into existence. Perhaps you have concrete evidence that shows this actually happened (not might have happened). Please don’t bring made-up stories or any interpretations of observations that require any assumptions, since stories and assumptions prove nothing."

Believe it or not, the comment of Sandy was on an Atheist website that was teaching logic. Yikes! The person who wrote the website was claiming that name-calling is not an ad hominem attack because of the fallacies that are quoted by sandy. That website used the name, Tony instead of Roxanne, but we are trying here to maintain a parable of sand versus rock, so we changed it to Roxanne.

Sandy probably won’t get it, but Roxanne has quietly countered two other fallacies contained in Sandy’s argument. The first is the logical fallacy of equivocation on the word, evolution. There is no issue regarding the fact that every kind of living things varies from generation to generation. This is observed. What is not observed is molecules-to-man evolution or any kind of living thing turning into any other kind of living thing over time. Sandy ought to bring forth evidence of this kind of evolution having taken place from a single-celled organism to all the various kinds of living things that now exist. That, however, has proven to be unverifiable. The second fallacy underlies evolutionistic thinking and is rarely mentioned. That is the fallacy that proving that evolution is possible (which has never been done) would then prove that evolution actually took place. Evolutionists simply assume that evolution took place. They never show proof that it did. Instead, they tell stories about how it could have possibly happened, but they use presumptive language. This is the logical fallacy of presumption. Where would a conversation like this go?

Sandy: "You can't claim revelation. You are assuming revelation but it is just presupposition, so we are on equal ground."

Roxanne: "Now you are again presuming that the revelation that I and all who follow Christ is nothing but presupposition, but you have offered no proof. Please explain the process by which you determine that revelation is presupposition."

Sandy: "I just don't believe it."