This is a BIG problem for Atheists, Agnostics, and Skeptics. It means they can’t be rational, but they love to think of themselves as the rational ones. Rational thought is not an option for them.
Two-thousand years ago, Agrippa the Skeptic realized that the human mind has no way to reason to truth. What he discovered destroys science, philosophy, and all human thinking. Rational thought must be based on truth, but the human mind can’t reason to truth. Humans can observe imperfectly and incompletely, but they can’t reason about what they observe unless they can get truth from outside themselves. Since Agrippa didn’t know Jesus Christ, the only Source of all truth, Agrippa assumed no truth could be known. Of course, if no truth could be known, then Agrippa couldn’t know that no truth could be known. It’s a terrible problem.
Fortunately, God has provided a way we can know the truth. God’s way is called divine revelation. God speaks to every person. He reveals natural reality and spiritual reality. Romans one says He reveals everything that can be known about God and the Godhead, and He makes it plain through the things He has created. It takes a hard heart to look up at the night sky without sensing the divine presence. He speaks through the Bible and every means of divine revelation mentioned in the Bible. He speaks through prophecy, a word of wisdom, a word of knowledge, a still small inner voice, angels, conscience, intuition, and Christians who are speaking by the Holy Spirit. We’re learning to discern His voice from all others. As we mature in Christ, Christ is formed within us and our deceptive fleshly nature decreases. The second letter to the Corinthians tells us, in the third chapter, about the fleshly veil that keeps us from hearing God’s voice even when He speaks to us through Scripture. However, It also tells us that the fleshly veil is taken away when we turn to Christ. In those moments when we look away to Jesus, our vision clears. We see reality as it is. We know the truth. We can be rational. Right now, those glimpses are precious. They may be few and far between. We may get wrapped up in our doctrines as the Jewish people did. We may be so convinced of our presuppositions that they seem real to us. God’s plan is that we come into the presence of Christ and stay there seeing reality and flowing with His wisdom. If we listen to the voice of Jesus, He will be our teacher. Then, we will know the truth, and the truth will set us free from all sin.
This trilemma goes by several names. It’s Agrippa’s Trilemma. It’s also the Münchausen Trilemma. Schools don’t teach it or teach it in an irrational way because it defeats every godless form of thinking. Philosophers have tried to find ways around this trilemma over the centuries but have all failed. Every once in a while, someone comes up with a supposed “solution,” but there is no solution other than truth. And there is no Source of Truth other than Christ. Fortunately, anyone can know Jesus Christ.