We think of ghosts as wispy and translucent — a vaporous woman, perhaps, who floats down the stairs, her dress trailing in the languid air behind her. But in early modern Europe, ghosts were often perceived as solid persons. The viewer discovered that they weren’t when they did something that ordinary humans could not, like bypassing a locked door to enter a room. By the 19th century, people had begun to think of ghosts predominantly as spectral forms — ephemeral, elusive, evanescent. When the ghost of Marley appeared to Scrooge in Dickens’s A Christmas Carol (1843), and Scrooge looked his transparent body “through and through”, he illustrated a shift in the ways ghosts became real to people, how ghosts were seen and remembered.
In Spectres of the Self, the cultural historian Shane McCorristine points to two reasons for this transmutation. The first was scepticism about the supernatural, generated by the new developments in science. The concept of hallucination emerged to explain experiences like seeing an apparition. As the seeing of ghosts became a psychological phenomenon, it also became a pathological one. In 1848, the British sceptic Charles Ollier spoke for many when he wrote that “anyone who thinks he has seen a ghost, may take the vision as a symptom that his bodily health is deranged”. As a result, McCorristine writes, the ghost was gradually relocated “from the external, objective and theological structured world to the internal, subjective and psychological haunted world of personal experience”.
The other reason was the development of new technologies, including photography in the early decades of the 19th century. Those who wanted to hang on to their belief in the supernatural despite the apparent threat posed by science found in the idea of the hallucination a kind of scientific evidence that the dead came back to life. By the 1860s, “spirit photography” presented astonishing images of people alongside dead relatives, using double exposure and other manipulations to portray a gauzy form alongside living flesh. It was the transparency that marked the dead as dead — and of course, it was technology that allowed some photographers to fake the ghost.
Pop culture is richly peopled with vampires, zombies, the living dead: the Harry Potter books, the Twilight series, the television show Grimm. Scholars sometimes talk about this supernaturalisation as a kind of “re-enchantment” of the world — as a growing awareness that the modern world is not stripped of the magical, as the German sociologist Max Weber and so many others once thought, but is in some ways more fascinated than ever with the idea that there is more than material reality around us. In part, I think, this is because scepticism has made the supernatural safe, even fun. It turns out that while many Americans may think that there are ghosts, they often don’t believe that ghosts can harm them.
There is, however, a deeper reason. Just as spiritualism became a means to hold on to the supernatural claims of religion in the face of science in the 19th century, the supernaturalism of our own time may enable something similar. Perhaps technology plays a role as well. Our world is animated in ways that can seem almost uncanny — lights that snap on as you approach, cars that fire into life without keys, websites that know what you like to read and suggest more books like those. The internet is not material in the ordinary way. It feels somehow different. Maybe this, too, stokes our imagination.
Luhrmann is an anthropologist and a contributing opinion writer The New York Times