Bill Jenkins is Research Fellow in the School of History at the University of St Andrews. He is working on the natural philosophy strand of the After the Enlightenment: Scottish Intellectual Life, 1790-1843 project with the School of History. He is the author of Evolution Before Darwin: Theories of the Transmutation of Species in Edinburgh, 1804–1834,  published by Edinburgh University Press in October 2019. He is interviewed by contributing editor Brendan Mackie about his article, “Physiology of the Haunted Mind: Naturalistic Theories of Apparitions in Early Nineteenth-Century Scotland” that appeared in the most recent issue of the Journal of the History of Ideas (October, 81.4).

This interview was conducted, edited and condensed by Brendan Mackie then reviewed by Bill Jenkins.


Brendan Mackie: So, so to start off, set the scene for me. Tell me about nineteenth-century rationalist Scotland, and why they have problems with ghosts?

Bill Jenkins: First we need to go back to the previous generation of Enlightenment scholarship. There were a number of very big names in the philosophy of the time, including the disciples of the Common Sense philosopher Thomas Reid, like Dugald Stewart and Thomas Brown. They were still alive in the early years of the century when a lot of the protagonists of my story were students in Edinburgh. The important part of their legacy was this belief that reason was the key to unlocking the secrets not only of the natural world, but also the human mind as well.

Brendan Mackie: So why are apparitions—ghosts—a problem for this rationalist project? Personally, I don’t think ghosts exist. So I don’t feel the need to have scientists and philosophers try to ‘solve’ the problem of ghosts and go off to haunted houses with ectoplasm detectors or whatever. But why were ghosts in nineteenth-century Edinburgh a problem for these people who believed in the power of reason to explain the natural world and the human mind?

Bill Jenkins: This was a period when there was a lot of interest in the supernatural. In Scotland there were a large number of people who genuinely believed that ghosts did actually exist, and that other spiritual beings did visit us from time to time.

We can think of this a period when faith in the rational order had been undermined, to a certain extent. Some thinkers, for example, linked the rationalism of the eighteenth century to the French Revolution, and the threat of breakdown of the social order in Britain and Scotland in particular. This led to a breakdown in the faith that reason was the answer to everything. People were more open to ideas about ghosts and other forces that were not amenable to rational explanation.

Brendan Mackie: So we have this eighteenth century rational project where people like Thomas Reid are saying that the whole world—both natural phenomena and social phenomena—can be understood rationally. But after the excess of the French Revolution, people get freaked out. Maybe explaining every single thing in the world rationally both doesn’t work—and can lead to excesses like the guillotine. As a response people are more open to the idea that both the natural and social worlds are resistant to reason. But did this have a practical effect? Were people seeing ghosts all the time? Talking about ghosts? Writing about ghosts?

Bill Jenkins: Now, I think it was something that was very much in the public mind in terms of the, let’s say, more intellectual middle class. There were ghosts stories and other supernatural tales in periodicals like Blackwood’s Edinburgh Magazine, for example. The work of Sir Walter Scott contained a strong supernatural element. And James Hogg one of Scott’s contemporaries—who is, to my mind, a much more interesting writer—wrote stories with a very strong supernatural theme running through them, including some of his best known ones like the Brownie of Bodsbeck or the Private Memoirs and Confessions of a Justified Sinner, his most famous book. So people were being confronted with the supernatural through literature to quite a significant extent.

There’s also the influence of evangelical religion, which was strong at the time. Evangelical religion places a much bigger emphasis on God’s intervention in the world and also the intervention of other spiritual beings. Many Evangelicals believed that the angels and demons actually made their presence felt in the world and had certainly made their presence felt in the past.

Brendan Mackie: So evangelicals were committed to the existence of the supernatural because it shows that God is alive in the world. This is in contrast to the rationalist god, who is constrained by the same rules everyone else has to follow. In the paper you quote the historian John Henry, who describes the god of these rationalist moderates as a “God who is hidebound by the laws of logic, whose omnipotence is compromised by the need to obey the same ineluctable laws as mankind, whether laws of logic, of nature, or of morals.”

Bill Jenkins: Yes, the distinction here is between what my colleague John Henry describes as the conflict between intellectualist and voluntarist interpretations. An intellectualist believes that God is actually constrained by the laws of reason—He doesn’t have absolute freedom to do anything he wants. Whereas a voluntarist believes that God actually makes the laws of reason, so he can break them, too. He can make two and two to equal five, if he wants to. God can act in the natural world completely without any reference to reason at all. Evangelicals tended towards that view. Whereas their opposition within the church, called the Moderates, tended to believe the opposite: that God works through secondary laws. He works with natural law, generally, and is bound by reason.

Brendan Mackie: What were some of this rationalist moderate responses to the problem of ghosts, then? How did they explain ghosts rationally?

Bill Jenkins: The most common response was to say that ghosts are a real phenomenon, but they are a phenomenon caused by dysfunction of the mind and the visual apparatus, caused by physiological dysfunction, that are in a sense a manifestation of mental illness, as we would now call it. They were looking at ghosts and apparitions as a medical issue, not a spiritual one. This was developed in various levels of sophistication, but Samuel Hibbert’s view and also the view of David Brewster, the natural philosopher who was one of Hibbert’s friends and who very strongly agreed with him on this, was that what effectively was happening was that when people saw ghosts, the visual organs were going into reverse. So instead of showing you what was happening in the outside world, images were actually being projected from the mind onto the retina of the eye from the brain via the optic nerve. That’s literally how they imagined it.

The Magic Lantern was a popular technology of the time and they imagined that this worked very much like a magic lantern: that the retina was a screen that you can project images onto. They could either come from the outside world through the eye or they could come from the other direction, from the brain, from the memory. This meant that they believed that if you looked into somebody’s eye while they were seeing a ghost, you would see the ghost on the person’s retina, being beamed out from the person’s brain.

Brendan Mackie: So the rationalist answer to ghosts is: look, these people who are saying that they see ghosts—they really are seeing ghosts. But they’re not seeing the spirit of a dead person, instead they’re having some problem with the plumbing of their eye. Instead of having the outside world go in, they have the inside world go out.

Bill Jenkins: Yeah. And this has some interesting implications. You tend to think of the subconscious mind has been something that comes along with Freud at the very end of the nineteenth century and the beginning of the twentieth century, but actually some of these ideas are in some ways quite analogous to the idea of the subconscious mind. Because this theory of apparitions assumes that there was always this stream of consciousness going on in our minds that we aren’t aware of, below the surface of thought. There’s this free association of images going on all the time in our minds, and every time it pops up to the surface, somebody sees a ghost.

Brendan Mackie: There’s a way that this rational explanation for supernatural phenomenon undermines the power of rationality itself. It explains ghosts as just this physiological quirk of your malfunctioning brain. But this makes the workings of the mind itself a lot more ghostly by saying that there are always ghosts in your head, but we just aren’t paying attention to them.

Bill Jenkins: Yeah, in this account, ghosts are literally coming from the unconscious mind.

Brendan Mackie: So why should you read your article? What does this tell us about other big ideas and intellectual life or the world around us?

Bill Jenkins: It’s actually very topical because we’re now going through a period when people are challenging the power of reason. We only have to look at the prevalence of the term fake news and the current distrust in experts in general to see that there is a contemporary challenge to the power of reason to explain the world. We’re seeing as well a rise in “irrational” beliefs like we saw in the beginning of the nineteenth caused I think by social dislocation of one kind or another. In the early nineteenth century it was the aftermath of the French Revolution and the threat of radicalism at home and people were reaching around for sort of answers to these questions and reason seemed to fail them. The social order didn’t seem to be rational and explicable in rational terms anymore. They couldn’t just dismiss the people seeing ghosts and say that these people were mad. They saw that reason itself was under threat.


Brendan Mackie is a PhD candidate at University of California, Berkeley, writing his dissertation on clubs and societies in 18th century Britain. You can find his podcast at historian.live. Subscribe to his mailing list to get updates whenever he writes a thing!

Featured Image: Engraving representing a “Phantasmagoria” from Mémoires récréatifs, scientifiques et anecdotiques du physicien-aéronaute E.G. Robertson : connu par ses expériences de fantasmagorie, et par ses ascensions aérostatiques dans les principales villes de l’Europe (1831). Courtesy of Wikimedia Commons.