The human mind, linguist Noam Chomsky argues, is a biological system with built-in limits. As impressive as the brain is, it is neither infallible nor capable of unlimited understanding. Recognizing these constraints, he suggests, helps us draw a crucial distinction between problems and mysteries. 

Problems fall within the scope of our cognitive abilities. We may not have solved them yet, but in principle, we can. These are the kinds of issues science is built to address—things like how language is structured, how cells function, or how planets move. They’re difficult, but tractable. 

Mysteries, by contrast, are questions that lie beyond our natural cognitive capacities. Just as a dog can’t understand calculus, humans may be biologically incapable of grasping certain aspects of reality. These aren’t just unsolved problems—they may be unsolvable for beings like us. Classic examples include the ultimate nature of consciousness, why there is something rather than nothing, and the existence or nature of God.

This distinction becomes especially relevant in the domain of religion—a point already recognized in antiquity by Marcus Tullius Cicero (106 – 43 BCE), the Roman statesman, lawyer, and philosopher. Cicero rose to prominence as one of Rome’s greatest orators and rhetoricians and did much to transmit Greek philosophy to the Roman world and beyond. In his book The Nature of the Gods—a comparative study of Epicurean, Stoic, and Skeptical theology, the last of which he most closely aligned with—Cicero offers the following observation:

On this question [the nature of the gods], the pronouncements of highly learned men are so varied and so much at odds with each other that inevitably they strongly suggest that the explanation is human ignorance, and that the Academics have been wise to withhold assent on matters of such uncertainty; for what can be more degrading than rash judgement, and what can be so rash and unworthy of the serious and sustained attention of a philosopher, as either to hold a false opinion or to defend without hesitation propositions inadequately examined and grasped?

The problems of science are well within our grasp, and if we spend enough time on them, we converge on increasingly precise answers. This is why there is no Eastern orthodox thermodynamics or Western reformed quantum mechanics; for the most part, physics is physics, and chemistry is chemistry, regardless of where you were raised and which language you speak. And where scientists do disagree—largely in matters of interpretation—it’s regarding questions that push up against the cognitive limits Chomsky identified.

Science, of course, is not infallible, and few would make that claim. But its laws have been carefully crafted within active systems of criticism, surviving enough attempts at refutation that we can provisionally treat them as reliable descriptions of reality. We don’t, for example, have to sort through rival versions of thermodynamics. There are four laws—well established and  extensively tested across a wide range of domains. You are free to challenge them if you wish, but doing so would require an extraordinary burden of evidence, and would be unlikely to be taken seriously within a scientific community governed by rigorous standards of proof. 

In matters of religion, things are very different. As Cicero wrote:

Indeed, there is no topic on which not merely the unlearned but even educated people disagree so much, and since their beliefs range so widely and are so much at odds with each other, two possibilities exist; it may be that none of them is true, or at any rate no more than one of them can be.

When Cicero wrote this, he was dealing with three major belief systems in his book and thought he pretty much covered everything important. If he were to write the same book today, it would require volumes upon volumes and this wouldn’t even scratch the surface of Protestant Christianity! 

Anthropologists estimate that humans have worshiped at least 18,000 distinct gods, goddesses, and sacred animals or objects. Today, roughly 10,000 regionally-based religions exist worldwide, and—according to the Center for the Study of Global Christianity—some 47,300 Christian denominations and rites were active as of 2023. 

If you listed all of the gods humanity has invented—with 40 names on each page—it would take 450 pages to capture them all—the size of a lengthy book. And this would leave out the competing interpretations of each god and all of the various doctrinal differences between religions, churches, sects, and individual people. 

Religious beliefs stretch across the entire spectrum of possibilities. If the convergence of scientific knowledge suggests we’re steadily approaching reliable understanding, what are we to make of the enduring—and often irreconcilable—divergence of opinion in religion? 

The more time we devote to a problem, the more we expect our understanding to deepen—that’s the mark of something genuinely tractable. We’ve spent millennia charting the motion of the planets, and the payoff is unmistakable: the marvels of modern astronomy and space travel. Yet we’ve invested a comparable amount of time reflecting on the nature of God—and it’s not clear we’ve advanced much beyond where Cicero stood.

As Cicero wrote:

Should you ask me to identify God or his nature, I shall cite Simonides as my authority: when the tyrant Hiero posed the same question to him, he asked for a day’s grace to consider it privately, and when Hiero put the same question to him next day, he begged two days’ grace. After doubling the number of days repeatedly, and being asked by Hiero why he did this, he answered: “The longer I ponder the question, the darker I think is the prospect of a solution.”

And that’s the nature of mysteries—they don’t yield, no matter how far we press. The longer we dwell on them, the less we seem to understand. This is the tragedy of human intelligence. “Human reason has this peculiar fate,” Immanuel Kant wrote, “that…it is burdened by questions which…it is not able to ignore, but which, as transcending all its powers, it is also not able to answer.” Humans are drawn to mysteries, yet desire certainty. It therefore takes a bit of courage to admit—regarding questions of great importance—that we simply don’t know. 

The first Western thinker to demonstrate this courage was Protagoras of Abdera, a 5th-century BCE presocratic philosopher and sophist, whom we will give the last word:

About the gods, I am not able to know whether they exist or do not exist, nor what they are like in form; for the factors preventing knowledge are many: the obscurity of the subject, and the shortness of human life.

More than 2,400 years later—and oceans of ink spilled—are we any closer to a better answer?

References

Benson, Dave. “Christian Denominations.” Lausanne Movement. Accessed February 19, 2026. https://lausanne.org/report/polycentric-christianity/christian-denominations.

Cicero, Marcus Tullius. The Nature of the Gods. Translated by P. G. Walsh. Oxford: Oxford University Press, 2008.

Sharif, Yahya A. “The Geography of Belief: Religious Affiliation as a Function of Birth, Socio-Psychological Imprinting, and its Implications for Truth Claims” (September 30, 2025). Available at SSRN: https://ssrn.com/abstract=5549164.

Wenk, Gary L. “Why Do Humans Keep Inventing Gods to Worship?” Psychology Today, 2021. https://www.psychologytoday.com/us/blog/your-brain-food/202107/why-do-humans-keep-inventing-gods-worship.