What is it like to have no visual points of reference? To experience the world with one of your senses edited out? To have grown up with no knowledge of colour or the look of a face? What inhabits the dreams of people blind from birth?
"Often a blind person experiences a series of veils: I stare at the world through smeared and broken windowpanes. . . I see like a person who looks through a kaleidoscope; my impressions of the world are at once beautiful and largely useless."
These are among the opening lines of American Stephen Kuusisto's book, Planet Of The Blind, which has just been published on this side of the Atlantic. Kuusisto has been partially sighted since birth, and his book is a lyrical, impressionistic exploration of a blurred world, where imagination fills in when his sight fails him.
There are currently 5,821 people registered blind in Ireland, according to the latest statistics from the National Council for the Blind in Ireland (NCBI). To be registered, a person can see only at six metres' distance what others can see from a distance of 60 metres.
Christina McCarthy has just turned eight. Her spaniel, Squeak, lies beside her on their sitting room floor and snores. "He seems to know that I can't see him," she explains shyly. "He gets out of the way when I'm walking around. The only time I might step on him is if he's asleep."
How does she choose her clothes? "By the way they feel. If they feel nice, and if they have things on the front, like this one." She points to the three flowers embossed on her pink sweatshirt. Her favourite book is The Secret Gar- den. "Because the children made lots of colourful flowers in their garden."
In the NCBI foyer shop, there are various items on sale: talking clocks, Braille playing cards and talking kitchen scales. There are also scented crayons and markers. The yellow smells of lemon; brown of cinnamon; orange of oranges; red of strawberry; black of liquorice. "I have those markers," Christina says excitedly. "I use them to make drawings. And I paint things and make other pictures." What does she draw? "Sometimes what I think Squeak looks like. Other times, I draw things out of my head. People look at them and they tell me what they see in them."
She fetches one of her pictures: a piece of transparent, plastic-like material, on which she has etched out a drawing. She runs her fingers over it. "This one has hills in it. And a farmhouse," she says with assurance, handing it over. Afterwards, examining it more closely, I discover lots of vertical lines. Are these the hills? No amount of peering reveals a house to me, but Christina's understanding of what a house looks like is in there somewhere. Listening to Christina talk about what people see in her drawings is to be reminded of the way people talk to each other when they point out the various pictures and shapes they can see in cloud formations: what you see depends entirely on yourself and your imagination.
Tony Murray (17) used to cycle his bike all around the neighbourhood when he was growing up. "I fell off the odd time, but no more than anyone else," he reports with a grin. He also played football. "We had a special ball that rattled, so you could hear when it came near you. We were very competitive." Tony is now in his first year at Dundalk RTC, studying computer software development.
As a child, reading fairy tales, his impression of a monster was "never something big. My monsters were always small. I suppose they were toy-sized, on the scale of what I knew."
Does the concept of Dublin as a Georgian city mean anything to him? Tony shakes his head. "No. I've never felt any models of a Georgian house. But I've been in New York and the streets there definitely felt different to Dublin. The streets there felt closed in and the air didn't move."
What he would be most curious to see are mountains. "I have no idea of size on that scale. People are great at trying to describe things to me, but mountains are something about which I really still have no idea."
"For somebody who is blind, language is what paint and colour must mean to someone who is sighted," says Audrey Tormey (27), who is a teacher. "For me, colours are redundant language; meaningless." She studied French, Spanish and Philosophy at UCD, and then did her H. Dip.
Audrey has owned a camera for many years. "I know it sounds astonishing, but I'm fascinated by images, even though I can't see them myself," she explains. "I bought my camera partly out of curiosity. I wanted to capture on film what sighted people see: capture my own perspective on the sighted world. When the pictures come back, someone will look at them and tell me what's in them."
She points out that she is able to show new friends photographs of past holidays and family occasions like Christmas: precisely the same reasons that many other people take pictures.
"Sometimes I take them by listening to where people are. And sometimes I won't know what I'm photographing. It's always a surprise when the pictures are developed."
Like Tony, Audrey is flummoxed by perspective and scale. "I can't understand how you can take a picture of something which is supposed to be as big as the Eiffel Tower and it will fit into the same space as a picture of a person. That to me is a mystery."
She goes to the cinema a lot. When you don't have a clue what Brad Pitt or Daniel Day-Lewis look like, what makes a film star attractive? "Their voice. For me, it's Liam Neeson, without a doubt." As for films: "Obviously it's better when there's a lot of dialogue." Then she says gleefully, "Horror films are great. They have such atmospheric music, it's easy to follow the story. And I don't get too scared because I can't see what's happening."
Joe Bollard (62) was born with normal sight. At the age of two-and-a-half, an operation to remove a growth from deep within his ear went wrong. The optic nerve to his left eye was severed and the following day, the other eye became sightless also. Although so young at the time, he says he remembers: "The sun - a big yellow thing in the sky that seemed to be all over the place. And the colour red. My mother had a red coat."
Before he went blind, Joe had regularly accompanied his father on fishing trips. They used to take the train from Westland Row to Greystones. "That journey is the last memory of sight I have. And now, when I get very tired, I fall asleep and always dream the same dream - a sort of nightmarish dream. I dream that I'm on a train, and the poles are rushing by and I can smell the steam and everything is red. Always red."
Although he has been married for years, Joe says he has "no idea at all what colour my wife's hair is. Maybe I asked her once, but I don't remember what colour she told me. It's of no interest to me, even in theory. Her eyes? No, I couldn't say what colour they were either. But all that stuff is only the box. It's what's inside the box that matters."
The first memory which Emer Mulhall (29) had was of "standing in a doorway and my mother singing a song about a bird flying. And I didn't know what a bird was, or how it could fly. I still have no idea how a bird manages to fly." Emer was born with abnormally small eyes, "which never worked. The first time I realised I was different was when I kept crashing into furniture, when I was about three."
Like Audrey, Emer also thinks Liam Neeson has a wonderful voice. Then she laughs. "I'm as bad as sighted people in making instant judgements about people. But for me, it's based on how someone sounds, rather than on how they look."
However, she prefers the theatre to cinema. "A play like Frank McGuinness's Observe The Sons Of Ulster Marching Towards The Somme makes me feel as if I'm in the middle of it all. And the sound is so much more textured: the voices just come at you as they're spoken, instead of coming out of cinema speakers."
After studying English and History at Trinity, Emer now works at the NCBI. She uses a cane to help her get about. "But in my dreams, it never appears. There are never canes or guide dogs in my dreams."
She has never been swimming in the sea. Why? "I've been paddling. But I suppose I was afraid to go in properly. I have this idea of all the ocean life being all around me straight away, and that I would be surrounded by lots of fish as soon as I started swimming." There's something familiar-sounding about this description. Later, I realise that Emer's impression of the sea as a block of water dense with fish is exactly the way a sighted person would describe an aquarium.
What would she most like to be able to see? "A lion. I've read a lot about Africa and I'm so curious to know what a lion looks like. No scale model or toy can give me that sense of power or of their movement, because they run fast don't they? What I would love is to go to the Natural History Museum, open up all the glass cases, climb inside them and feel the shapes of all those stuffed animals." Then Emer laughs, and says: "I wonder if I would know which one the lion was when I got to it?"
Planet Of The Blind, by Stephen Kuusisto (Faber and Faber, £9.99 in UK).
Out Of Sight, by Joe Bollard (Wolfhound, £7.99).