In The Man Who Mistook His Wife for a Hat Oliver Sacks offers an interesting neurological account of the visions of the great mystic Hildegard of Bingen. Sacks recounts one of Hildegard’s writings titled “The Fall of the Angels” where she describes witnessing the fall of Satan and his minions: “I saw a great star most splendid and beautiful, and with it an exceeding multitude of falling stars which with the star followed southwards … And suddenly they were all annihilated, being turned into black coals … and cast into the abyss so that I could see them no more.” (Cited in The Man Who Mistook His Wife for a Hat (London; Picador, 1986), 161).
Sacks then offers his own analysis: “Our literal interpretation would be that she experienced a shower of phosphenes in transit across the visual field, their passage being succeeded by a negative scotoma.”( 161) Fair enough, Sacks’ “literal interpretation” may be correct insofar as “literal interpretation” = an account of the neurological processes underlying Hildegard’s vision.
However, I suspect that by “literal interpretation” Sacks really intends to refer to “What was really happening.” In other words, Hildegard was experiencing a shower of phosphenes in transit across her visual field which she interpreted as falling stars. And that’s all there is to it.
Again, that may be. But let’s just be clear: that isn’t an argument. Rather, it is a reductive interpretation. In his modern classic The Clockwork Image: A Christian Perspective on Science (InterVarsity, 1974) Donald MacKay famously referred to the leap from “This is x” to “This is nothing but x” as “nothing buttery”.
But wait, what about Ockham’s Razor? Don’t multiple entities beyond necessity, right? So if you can explain Hildegard’s vision by appealing to that shower of phosphenes alone, why tag on a spiritual reality? Doesn’t the physical explanation render the non-physical otiose?
Possibly, but the fact is that we regularly adopt richer explanations if we believe our experience warrants that richer interpretation. For example, you could explain the rich panoply of conscious experience without positing a physical reality: after all, we could just be minds in the matrix. But even if we don’t have a rebuttal to reductive, idealistic accounts of conscious experience, most of us will happily dismiss such nothing buttery as insufficient. Consciousness may be sensory experiences in the mind, but one can believe it is also more than this. All Hildegard need do is apply the same principle to her visions: they may be showers of phosphenes, but that doesn’t mean that they can’t also be visions.