麻豆传媒

Jacqueline Yallop (Icon Books)

WE ARE all familiar with finding ourselves in the dark 鈥� physically, or metaphorically. Especially now, in late autumn in the northern hemisphere, it is part of daily life, when we turn off our bedside light to sleep or open the curtains to discover the gloom outside. But what exactly is the dark?

In Into the Dark: What darkness is and why it matters, Jacqueline Yallop sets out to answer that question and more. Her motive was to understand her father鈥檚 retreat into dementia, manifesting early as a sensitivity to shadow and light. Yallop ventures into the dark herself with late-night walks through coastal Wales, the rural Pyrenees and inner London and New York. The different characters and textures of those nighttimes highlight her challenge.

In the 1660s, Isaac Newton concluded that dark 鈥渋s an absence of light鈥�. But if so, how do we account for our experience of it? Even at night, we are still able to see, while quantum physics asserts that the total lack of photons is impossible. Yallop shows how centuries of investigation have brought little clarity, concluding that 鈥渄arkness is an anomaly鈥� 鈥� a complicated state that is intrinsically connected to sensory perception, but not one that can be readily trusted or explained.

Even people with impaired vision may experience blindness as continual, changing bursts of light. In the 鈥減itch black鈥� (first written about in 1598 by poet and playwright John Marston, referring to the tar used to waterproof ships) our brain will generate images to hold off 鈥渢he terror of utter darkness鈥� and discomfort of the void, says Yallop.

Here, yet another contradiction emerges: these visions may be quite as 鈥渞eal鈥� as any we actually see. In 2007, the German artist Marietta Schwarz was blindfolded for 22 days and studied by neuroscientists who placed her in an MRI scanner. When she recounted seeing, in her mind鈥檚 eye, the opening titles of Star Trek, the scanner showed exactly the same brain activity as if Schwarz was really watching the show.

Yallop shows 鈥渄arkness鈥� to be as much culturally mediated as a quantifiable reality: an experience, a change of state, even a feeling. Darkness can undo our sense of time and space, and even sanity.

As Yallop makes clear, darkness is loaded with associations. It is linked to seasonal change, rebirth, loneliness, loss of faith, ignorance, evil, eroticism, deviance, death. In pre-industrial times, darkness was often heralded 鈥� or 鈥渄riven out鈥� 鈥� by bells, horns or drums.

By the 15th century, households on London鈥檚 busiest streets were required to hang lanterns. As late as 1891, doctors warned in The Lancet of thoughts becoming 鈥渕ore extravagant in darkness鈥�, potentially inciting 鈥渁 form of nocturnal insanity鈥�.

Not all of Yallop鈥檚 leaps into the dark are equally interesting: for example, her emphasis on poets and painters grows repetitive, if understandable given her work as a cultural historian. But her forays into the past do shed light on a present that is increasingly intent on banishing darkness.

Light pollution is disrupting the circadian rhythms, migratory patterns and breeding cycles of many living things. Globally, wildlife is struggling to adapt.

Into the Dark might have benefitted from more on-the-ground, in-depth reporting from the dwindling places that are free of light pollution. I wish Yallop had been able to develop her ideas about her subject, perhaps by drawing parallels with the absence of other sensory inputs with a stint in the 鈥渜uiet chamber鈥� at Orfield Laboratories, Minneapolis 鈥揷onstructed to be the quietest place on Earth and somewhere that can be experienced in total darkness 鈥� or by visiting some of those far northern spots that spend months without the sun.

What she does do, though, is point out that not all peoples are so afraid of the dark. The M膩ori day begins with night, while its language has many descriptive words for darkness. And M膩ori academic Carl Mika has condemned the 鈥渃olonial fixation on clarity, visibility and enlightenment鈥�, calling for the West to embrace an open, benevolent view of the dark.

However, Yallop doesn鈥檛 seem willing or able to go there. But then she isn鈥檛 a journalist; instead, her book is often poetic while being highly-researched and thought-provoking. It is more testament to the slipperiness and intrigue of her subject that, for all the concepts and ideas she uncovers, more come to light.

Writer Elle Hunt is based in Norfolk, UK