Few arguments for the existence of God carry as much intuitive force as the appeal to religious experience. When a mystic describes an overwhelming encounter with the divine—a presence so vivid it reshapes everything they believe—it feels almost rude to ask for a receipt. The experiencer knows, with a certainty that seems to precede and surpass rational argument. And yet, this is precisely where philosophical scrutiny must be most unflinching.

The argument from religious experience, in its strongest form, holds that certain subjective states constitute genuine perceptual contact with a transcendent reality, and that these experiences therefore provide evidence—sometimes even decisive evidence—for theistic claims. William Alston's Perceiving God represents perhaps the most sophisticated version of this thesis, drawing an analogy between mystical perception and ordinary sense perception. If we trust our eyes, why not trust the mystic's inner vision?

The answer, as we'll see, is that this analogy collapses under the weight of its own contradictions. Religious experiences across traditions are mutually exclusive in their content. Neuroscience and cognitive psychology offer parsimonious explanations that require no supernatural causes. And there is a fundamental epistemic asymmetry between private experience and public evidence that the argument never adequately addresses. None of this means religious experiences aren't real as psychological events. They are. But being real and being evidence are different things entirely.

If religious experiences were genuinely perceptual—if they constituted veridical contact with an objective divine reality—we would expect a reasonable convergence in their content, just as we expect convergence among sighted observers describing the same landscape. What we find instead is radical, systematic divergence. The Hindu mystic encounters Brahman as an impersonal, all-pervading consciousness. The Christian contemplative encounters a personal God of love. The Buddhist meditator encounters śūnyatā—emptiness itself, the absence of any ultimate substance. These are not minor interpretive variations. They are mutually exclusive metaphysical claims.

Defenders of the argument from religious experience often appeal to a common core thesis—the idea that beneath the culturally specific trappings, all mystical experiences share a single ineffable referent. This was the strategy of writers like Aldous Huxley and, more carefully, W.T. Stace. But the common core thesis has been devastated by scholars like Steven Katz, who demonstrated that mystical experiences are constituted by their doctrinal and cultural contexts, not merely filtered through them. A Carmelite nun and a Zen roshi are not having the same experience in different wrapping paper. Their expectations, training, and conceptual frameworks shape what the experience is.

This creates what we might call the mutual cancellation problem. If a Christian's experience of Christ's presence counts as evidence for the truth of Christianity, then a Vaishnavite's experience of Krishna must count as evidence for the truth of Vaishnavism. But these traditions make incompatible claims about the nature of ultimate reality. The evidential force of one experience is neutralized by the evidential force of the other—unless one is willing to engage in the kind of special pleading that grants epistemic privilege to one's own tradition while dismissing everyone else's.

Richard Gale pressed this objection with particular clarity: the argument from religious experience can only succeed if we have independent reasons to privilege one tradition's experiences over another's. But those independent reasons would themselves need to be the real basis for belief, rendering the experiential argument superfluous. The experience adds nothing that the independent reasoning doesn't already provide. It becomes, at best, a psychological reinforcement rather than an epistemic foundation.

Some sophisticated theists, like Keith Ward, have tried to embrace religious pluralism—accepting that different traditions access different facets of a single divine reality. But this move requires abandoning the specific doctrinal content that makes each tradition's experiences seem so compelling in the first place. A God who is simultaneously personal and impersonal, trinitarian and non-dual, is not a coherent object of perception. It is a philosophical placeholder designed to avoid an uncomfortable conclusion: that the diversity of religious experience is better explained by the diversity of human minds than by any external referent.

Takeaway

When contradictory experiences all claim the same epistemic authority, they collectively undermine each other. Diversity of testimony is a strength for empirical claims precisely because perceptions converge; in religious experience, they systematically diverge.

The past three decades of neuroscience have produced an increasingly detailed account of how the brain generates experiences that feel transcendent without any external transcendent cause. Andrew Newberg's neuroimaging studies of meditating monks and praying nuns revealed consistent patterns: decreased activity in the posterior superior parietal lobe—the brain region responsible for maintaining the boundary between self and world—correlated precisely with reports of unity experiences and ego dissolution. The mystic's sense of merging with the infinite has a neural signature, and it is entirely internal.

Michael Persinger's work with transcranial magnetic stimulation of the temporal lobes demonstrated that experiences of a "sensed presence"—interpreted by subjects as God, angels, or deceased loved ones depending on their cultural framework—could be reliably induced in laboratory settings. While Persinger's specific methodology has been debated, the broader finding has been replicated in various forms: temporal lobe epilepsy, sensory deprivation, extreme fasting, rhythmic chanting, hyperventilation, and psychedelic compounds all produce experiences phenomenologically indistinguishable from those reported by mystics across traditions.

This matters philosophically because of what it does to the explanatory landscape. When we have two candidate explanations for a phenomenon—one requiring only known neurological mechanisms and another requiring an unobserved supernatural entity—Ockham's razor cuts decisively. The naturalistic explanation is not merely simpler; it also has independent empirical support, makes testable predictions, and coheres with everything else we know about how brains produce conscious experience. The supernatural hypothesis does none of these things.

Alston anticipated this objection and argued that showing a natural mechanism doesn't disprove a supernatural cause—after all, God could work through neural pathways. This is technically true but epistemically vacuous. By the same logic, one could argue that God causes all visual perception through the optic nerve, and that the neurological explanation of sight doesn't rule out a divine visual artist arranging every photon. The point is not that naturalism disproves the supernatural explanation, but that it renders it explanatorily idle. It does no work that isn't already done by the neuroscience.

There is also the well-documented phenomenon of apophenia—the human tendency to perceive meaningful patterns in noise, agency behind events, and presence in solitude. This is not a bug but a feature of evolved cognition: our ancestors who over-attributed agency (hearing a predator in every rustling bush) survived at higher rates than those who under-attributed it. The hyperactive agency detection device, as cognitive scientists of religion like Justin Barrett have termed it, provides a powerful and parsimonious account of why humans so readily experience invisible agents. Religious experience sits comfortably within this broader cognitive architecture.

Takeaway

An explanation that invokes only known mechanisms and makes testable predictions will always be preferable to one that adds an unobservable cause on top. Naturalistic accounts don't merely compete with supernatural ones—they make them unnecessary.

Perhaps the deepest difficulty with the argument from religious experience is structural. Religious experiences are, by their very nature, radically private. They cannot be shared, demonstrated, or independently verified. The mystic can describe what happened, but the description is not the experience. And the experience, being unobservable by anyone else, cannot function as public evidence in the way that empirical observations can.

This is not merely a practical limitation—a problem we might solve with better technology. It is a principled epistemic asymmetry. When a scientist reports an observation, the result can, in principle, be replicated by any competent observer with the right equipment. The observation's evidential force depends on this intersubjective accessibility. Religious experience lacks this feature entirely. When Alston draws his analogy between mystical perception and sense perception, he elides the fact that sense perception is checkable. I can verify your claim that there's a red car outside by looking out the window. No analogous procedure exists for verifying your claim that God spoke to you in prayer.

This creates what C.D. Broad identified as the problem of epistemic authority. Even granting that the experiencer is rational and sincere, their testimony provides at best weak evidence to the non-experiencer. The experiencer has access to a datum that the audience fundamentally lacks. This is not like trusting an astronomer's report of a distant galaxy—I could, in principle, look through the telescope myself. The mystic's "telescope" is their own subjective state, and it admits no second observer.

Some philosophers have argued that this is merely an instance of the broader problem of other minds or the reliability of testimony. But the analogy is strained. Ordinary testimony gains its credibility from systematic background checks: testimonial claims can be verified, patterns of reliability established, liars caught. For mystical claims, there is no independent verification procedure—only more testimony, which suffers from the same limitation. We are left not with a web of mutually reinforcing evidence, but with an echo chamber of unverifiable private reports.

The honest conclusion is this: a religious experience may be entirely rational for the person who has it as a basis for personal belief—what philosophers call de se justification. But it cannot bear the weight of a public truth claim about the fundamental nature of reality. To insist otherwise is to demand that others accept your private experience as their evidence, which is precisely what we refuse to do in every other domain of inquiry. If a colleague told you they could see an invisible dragon in the corner, the appropriate response would be compassionate curiosity, not metaphysical revision. The same epistemic standard should apply when the invisible entity is labeled "God."

Takeaway

An experience that cannot, even in principle, be checked by anyone other than the person having it may justify private belief but cannot ground a public truth claim. The gap between personal conviction and shared evidence is not a technicality—it is the foundation of rational inquiry.

The argument from religious experience is not trivial. It speaks to something real about human consciousness—our capacity for awe, self-transcendence, and states of profound meaning that defy ordinary description. Dismissing these experiences as mere delusion would be as philosophically careless as accepting them uncritically as divine revelation.

But evidence requires more than intensity of conviction. It requires convergence, intersubjective accessibility, and resistance to more parsimonious alternatives. On every count, religious experience fails the test. The contradictions across traditions, the availability of naturalistic explanations, and the irreducible privacy of the experience itself all converge on the same conclusion: these states tell us something fascinating about the human brain, but nothing reliable about the cosmos.

This need not be a diminishment. A sunset is no less beautiful for being explicable by atmospheric physics. And the human capacity for transcendent experience remains remarkable even when its explanation is entirely natural. The task for secular philosophy is not to deny the experience but to understand it honestly—and to build frameworks for meaning and wonder that don't require unsupported metaphysical commitments.