The argument from religious experience

What it is

Across every culture and every century, people report experiences of something they take to be ultimate: presence, unity, being known, an overwhelming love, a dissolution of the self, an encounter with a person or a light or a silence. They report these as perceptions, not as feelings or ideas — as though something were there and they met it.

The argument from religious experience holds that these reports are evidence for what they appear to be evidence of. Not proof, and not evidence available to anyone who has not had one, but genuine evidential weight rather than mere noise.

The counter-argument holds that a vivid experience of something establishes nothing about whether that something exists outside the person having it, and that there are ordinary explanations for why brains produce such states.

Where it came from

William James put the subject on a serious academic footing with The Varieties of Religious Experience (1902). His approach was to gather first-person accounts and treat them as data to be examined rather than as claims to be adjudicated, and he identified features that recur across traditions — ineffability, a sense of gaining knowledge, transience, passivity. He was personally undecided about their ultimate cause, which is part of why the book has lasted.

The modern philosophical form is largely Richard Swinburne's. In The Existence of God (1979) he proposed the Principle of Credulity: if it seems to you that X is present, then probably X is present, unless there are specific reasons to doubt it. This is simply how we treat ordinary perception — you do not demand independent corroboration before believing there is a chair in front of you — and Swinburne argues that carving out a special exception for religious perception requires justification rather than being the obvious default. William Alston developed a related case in Perceiving God (1991), arguing that religious experience functions within a practice with its own internal checks, much as sense perception does.

How it is used

In apologetics it functions as the argument that does not depend on cosmology or design — it appeals to something a great many people have directly, rather than to a chain of inference.

In comparative religion it does different work, as the basis for claiming that the traditions are describing one reality in different vocabularies. That claim is contested, and the argument over it — perennialism against constructivism — is substantial enough to need its own article.

What we can and cannot say

We can say the experiences are real as experiences. Nobody serious disputes that people have them, that they are often the most significant events of those people's lives, and that they frequently produce durable changes in behaviour that outlast any emotional afterglow. James thought the fruits were the most interesting evidence, and that remains defensible.

We can say the diversity objection has force. The experiences do not deliver a consistent message. Theists meet a personal God, Advaitins report the dissolution of any distinction between self and Brahman, Buddhists report no self and no God at all, and each is as certain as the others. If the experience is a perception of what is there, it is a strikingly unreliable one. Defenders answer that perception is always shaped by the concepts brought to it — which is true, and which also concedes a great deal.

We can say the neuroscience is more interesting and less conclusive than either side claims. The most famous result went the wrong way for the sceptics: Michael Persinger's "God helmet" experiments, which appeared to induce sensed presences with weak magnetic fields, failed to replicate — Granqvist and colleagues in 2005 reproduced the reported effects using suggestibility alone, with the field switched off. Meanwhile psilocybin studies at Johns Hopkins and elsewhere reliably produce experiences that participants rate among the most personally meaningful of their lives, and which resemble the classical mystical reports closely.

Which brings the sharpest point, and it cuts against a common assumption. Finding a neural correlate does not debunk an experience. There is a brain state associated with seeing a tree; nobody concludes the tree is imaginary. Every perception has a mechanism, and pointing to the mechanism does not settle whether anything was perceived. The genetic fallacy is a fallacy in both directions — a cause is not a refutation, and equally, an experience having a profound feeling attached does not make it veridical.

What we cannot say is that this is settled. The Principle of Credulity is a serious argument that has not been dismantled, the diversity objection is a serious objection that has not been dissolved, and the honest position is that a great many people have encountered something and we do not know what.

Further reading

• William James, The Varieties of Religious Experience (1902) — free, readable, and still the best entry point to the whole subject.
• Richard Swinburne, The Existence of God (1979), chapter 13 — the Principle of Credulity from its source.
• Granqvist et al., "Sensed presence and mystical experiences are predicted by suggestibility, not by the application of transcranial weak complex magnetic fields" (2005) — the replication failure that most popular accounts of the "God helmet" never mention.