Why does Bayesian reasoning favor natural explanations over supernatural ones?

1. Introduction to Bayesian Reasoning and Its Presuppositions

Bayesian reasoning derives from a formula that updates the probability of a hypothesis when new, relevant evidence is considered. This method requires an initial “prior probability,” which is then adjusted in light of additional data to yield a “posterior probability.” In many contemporary contexts, these prior probabilities often assume a naturalistic worldview, starting with the premise that supernatural causes are either extremely unlikely or impossible. Consequently, when evidence is introduced, the revised (posterior) probability of a supernatural event remains low if the initial assumption was to discount such a possibility.

However, it is essential to remember that presuppositions affect the entire analysis. If the prior excludes miraculous interventions, even compelling evidence for them will be filtered out. Those conducting Bayesian analysis from a standpoint that acknowledges divine intervention and the historical reality of miracles may arrive at vastly different results.

2. Historical Roots of Naturalistic Presuppositions

The roots of favoring natural explanations in Bayesian reasoning often trace back to the Enlightenment, a period in which philosophical thought elevated human reason and scientific inquiry above religious tradition. During this era, skepticism toward scripture and miracle accounts grew. Figures such as David Hume questioned the credibility of testimonies regarding the supernatural, arguing in his essay “Of Miracles” that uniform human experience weighs against such occurrences.

This skepticism still influences modern science, with many researchers or philosophers positing that if an event seems to have no natural explanation, it is prudent to await further data or hypothesize a yet-to-be-discovered natural mechanism, rather than accept a supernatural cause. This approach, while methodologically consistent within a materialistic framework, can appear closed off to contrary evidence when viewed within a theistic or biblically consistent worldview.

3. Scriptural Perspective on Supernatural Reality

Scripture frequently bears witness to divine intervention, portraying miracles not as anomalies but as God’s active engagement in the world. One example is in Exodus, where the Hebrew people experience the parting of the Red Sea (cf. Exodus 14). In the New Testament, miracles accompany Jesus’ ministry (Matthew 4:23: “Jesus went throughout Galilee, teaching in their synagogues, preaching the gospel of the kingdom, and healing every disease and sickness among the people.”). Such miracles demonstrate God’s willingness to step beyond the ordinary course of creation to accomplish His purposes.

Though these events cannot be reduced to purely natural processes, they are not presented as random anomalies but as sovereign acts of the Creator who shaped all natural laws. Consequently, a worldview informed by Scripture considers both regular patterns in creation—what we commonly call “nature”—and God’s sovereign ability to intervene in these patterns.

4. Why Bayesian Methods Often Reject the Supernatural

1. Starting Priors: Most Bayesian models in public discourse begin with the belief that everything must have a natural explanation. Consequently, the prior probability placed on supernatural occurrences is assigned a near-zero value. Inevitably, the posterior probability remains low when new evidence arises.

2. Lack of Familiarity: Many fields use Bayesian reasoning for repeatable scientific studies (e.g., drug trials, geological surveys). Supernatural events are, by definition, not reproducible on demand in a laboratory setting. Hence, from a purely scientific vantage point, these occurrences are less familiar and given less credence in calculations.

3. Cultural and Academic Norms: Higher education and research communities often entail methodological naturalism—seeking purely physical causes. This norm informs how data is interpreted, thus influencing the “likelihood” factor used to update probabilities.

5. Addressing the Apparent Conflict Between Bayesian Reasoning and Miracles

A. The Role of the Christian Worldview in Setting Priors

If the Creator exists, and Scripture is reliable, supernatural events are plausible because they align with the entire biblical narrative. Passages throughout the Bible affirm that God can and does intervene in human history, such as Hebrews 2:4: “God bore witness by signs, wonders, and various miracles…” Thus, one who begins with biblical truth grants a far more substantial prior probability for miracles, unlike a worldview that completely excludes them.

B. Cumulative Evidence and Miracles

In historical investigation, a single piece of data (like an inscription or an artifact) can appear inconclusive. However, the cumulative effect of multiple lines of evidence can shift probabilities significantly. For instance, multiple historical documents (including the Gospels and references by Josephus and Tacitus) affirm the existence, crucifixion, and rumored resurrection of Jesus. When these records are combined with archaeological and manuscript findings—such as the Dead Sea Scrolls and the Jerusalem tomb archaeology—they contribute to a stronger posterior probability for the events recorded in Scripture.

6. The Resurrection of Christ Under Bayesian Analysis

The historical evidence for the resurrection has been rigorously examined. The minimal facts approach (drawing on shared scholarly consensus, including Jesus’ death by crucifixion, the empty tomb, postmortem appearances, and the transformation of early disciples) can be integrated into a Bayesian framework. Without a default assumption against miracles, the resurrection emerges as a coherent explanation of the data.

As 1 Corinthians 15:3–4 states: “For what I received I passed on to you as of first importance: that Christ died for our sins according to the Scriptures, that He was buried, that He was raised on the third day according to the Scriptures.” The early creed in 1 Corinthians testifies to a belief in the resurrection that originated among the closest followers of Jesus, who claimed to have witnessed Him alive—an event difficult to explain purely on natural grounds if one considers their willingness to suffer and even die for that testimony.

7. Overturning Naturalistic Biases Through Evidence

A. Archeological Support

Ongoing archaeology consistently validates biblical places and customs, from the Hittite civilization once doubted by historians, to the Pool of Bethesda in Jerusalem (John 5), which was discovered in the 19th century. Such confirmations legitimize the historical reliability of Scripture. When the historical context of miracles is established as authentic, the supernatural aspects become more plausible under updated priors.

B. Scientific Findings and Design

Research into areas like the irreducible complexity of biological systems and the fine-tuning of the universe (explored in the fields of astrophysics and molecular biology) suggests patterns that point beyond mere chance. If the cosmos bears intrinsic marks of purpose, then the God who created it may logically intervene with miracles, including healings and resurrections. These reasoned observations can significantly affect the way individuals assign probabilities in Bayesian reasoning.

8. Invitation to Further Reflection

Bayesian reasoning does not inherently dismiss the miraculous; it only reflects the assumptions and parameters set at the beginning. Those open to biblical testimony and historical evidence may find that divine intervention is not only probable but also the most coherent explanation for certain events.

The question “Why does Bayesian reasoning favor natural explanations over supernatural ones?” ultimately highlights the power of starting assumptions. If one’s prior excludes God from the picture, the final calculation will follow suit. However, if one grants the historical reliability of Scripture and acknowledges an eternal Creator, there remains solid ground for concluding that supernatural explanations sometimes better account for the evidence than purely naturalistic alternatives.

In all these considerations, the broader testimony of Scripture underscores that God operates both through natural laws and in ways that supersede them. As Psalm 77:14 declares, “You are the God who works wonders; You display Your strength among the peoples.” Recognizing these wonders opens the door to embracing a more balanced approach that incorporates the best of logic and recognizes the reality of the supernatural as attested by Scripture, history, and experience.