Sight, language, reference and memory are contingent, rely on our agreement to shared understandings. Does what I see differ from what you see? You may read that number-plate which is a blur to me, or I think this scarf is green when you insist it’s blue. Yet the interior experience of vision is as unknown as the inside of the sun, reflected through our words and experience, measured abstractly by ever more specialised machinery. How do we know we share meaning: is grue real?
We can look directly at neither our own eye nor the nearest star. Carbon dioxide is invisible to our unaided sight, and glaciers melt too slow to watch. Four million fur seals are still vulnerable even as we hear them barking in the night. We may measure where we cannot see; facts cannot rely on embodied experience.
Helioseismologists listen to the music of the Sun by studying sound waves which bounce around inside. Ground telescopes and satellites, chromographs and X-rays, a dazzling, dazzled array of complex instruments. We study the interior of the star to understand how the sun works – how, like heat and light, its impact on our magnetosphere and atmosphere are crucial to life on Earth. Yet you cannot look at it straight on with physical danger but must mediate knowledge through unseen waves and machines in orbit.
We use instruments for our eyes too: opthalmascopes and the auto-refractor keratometer, an ocular Coherance Tomography scanner, or the comprehensible yet mysterious slit lamp are just the start. An expert watches screens to measure angles, distances, refractions, viscosity, detachments or pressure. She takes pictures, like this one of my own eye. She looks for disease (the feared macular degeneration, iritis, glaucoma or those pesky cataracts) but much of her effort is put into understanding how to improve that elusive experience: vision. We read off letters, compare red to green, judge different degrees of blur. The eye is the outside of our brain: what we see is what we think we see.
Jurisprudence has wrestled with the reliability of eye-witnesses. We know that emotion burns images into us, yet the amygdala and its relation to memory is still be understood. (The brain lobe is named via the Latin for almond ,while ‘mandala’ comes from the Sanskrit for disc; their apparent resemblance is misleading.) Throughout the 20th century lawyers looked at cases where the witnesses proved wrong: today in the UK, such testimony is problematic and instead we rely on our millions of surveillance cameras. The eye of the camera is more reliable than human sight.
We privilege sight, that most ubiquitous of senses. When people converse in their day-to-day lives, they often speak about what they hear, smell, taste or feel. First and foremost, however, they talk about their visual perceptions…. [researchers studying 13 languages] found no evidence of a fixed hierarchy of the other senses in the speakers’ linguistic usage… the hierarchy of the senses is shaped by both biological predispositions and cultural influences. Yet the Western concept of the ‘nobility of sight’ is not unchallenged: arguments have been made for the importance of taste and smell in Renaissance Europe, the folk- taxonomy of other senses to organise the natural world and the lamentable dismissal of crafts rooted in the sense of touch.
Despite the challenge, none of those other senses avoid the problems of meaning and unreliability. Save hearing, there is no ready replacement, no smell-capture to determine who really made a mistake in the lift, or velvetorium to record the specific experience of hair-shirt. For our ears and eyes, we use the technology to support our memories. For the rest, we have only words, our public language.
We connect memory to identity, inextricably entwined even if the connection is not always understood. If your memory fails, are you still the same person, asks the essayist. If I cannot recall you, have we met? Our identity then, is linked to our memory and our memory to those unreliable senses, the primal sights and sounds around us, locked into our shared and fractured discourse. As we give up expecting the news to be even approximately true, identity politics take hold. Humean scepticism notwithstanding, the sun rises every morning,; there is a reality on which to keep a grip, the hard truths of shared perception, historical experience and falsifiable experimentation.