Isabel Darrow sat across from Dr Lyndhurst, watching him as he stared back at her. He waited for her to speak - as was his wont - but she seldom uttered a word. She did not like to speak of her feelings; she had no wish to dwell on them, let alone share them with another, and yet she could not but ruminate on all that she had seen and felt; all that she had lost and failed. The thoughts filled her mind until she felt she did not truly know herself. Her head felt heavy and fuggy, her limbs numb and cumbersome, despite her compact, lithe frame, which combined a wily mix of strength and agility for one so small as she.

She had kept to her usual appointment - a Thursday afternoon - as she had for the past four months, and still she did not speak. Dr Lyndhurst sighed, and crossed one long leg over the other, his brow tugging downwards into a contemplative frown.

'Isabel? We have only another twenty minutes, and you are yet to speak more than a dozen words to me.'

'What do you wish me to say?' asked she, her expression clearing; her eyes shining with the hint of a sardonic smile. The doctor could not help but smile at her in return. She was a pretty thing, he thought; one who would be full of life and laughter if given half the chance, but she had never had such a chance - he knew that from her notes. He sighed and quirked his eyebrows in challenge.

'Is it not what I wish to discuss which is important, but what you should like to talk of.' She scowled at him; she did not wish to share her inner thoughts. Biting his lip to mask his frustration, Dr Lyndhurst cast his eyes over the blank page in his notebook. He could almost laugh at the shameful waste of paper. Every week he would write her name in the top right-hand corner of the page, date it, and wait expectantly for something to record in ink, but she offered nothing; she was caged and impenetrable. Of course, he had notes on her past; on what had happened earlier that year - the army had provided those - and he had a crude history of sorts, which told him of her troubled early years. From these papers - written by another's hand - full of another's suppositions and incites - he could infer a certain malady; a weakness of the mind, but how to heal that weakness; how it would show itself - that, he could not predict or suppose.

'Are you happy, Isabel?'

'Happy!' cried she; her tone incredulous. 'Why ever should I be happy?'

'You are alive; is that not something to be grateful for?' came his passive reply. Her lip curled and she shook her head a fraction. He could almost say that she was laughing at him, but he knew her not to laugh; he knew her to feel no warm feelings or moments of light relief, for surely, she would speak if she did. The warmth within her would be enough to burn through her icy cage and words would slip out; answers and secrets trickling from her like droplets of melting snow.

'Grateful, indeed -' she mused under her own breath, but Dr Lyndhurst's ears were attuned to such low-spoken admissions, and he had his first honest reply in some sixteen weeks' of meetings.

'You are not glad to be alive? To have been able to return home? Surely you feel the privilege, where others close to you did not?' He was trying to provoke her, for now he had found her weakness; a crack in her façade.

'Am I alive? Is this home?' she asked, her hazel eyes meeting his own green ones; piercing in their intent. Dr Lyndhurst shifted in his seat; his excitement rising.

'You do not call Kent "home"?' asked he, tackling the question he knew would be easy for her to answer.

'I call nowhere home. What is home? Where one rests one's head? Surely not, for the word "home" says, to me, far more than any meagre surface - soft or hard - upon which one may place their skull. It says to me a place where one belongs; where one is free to be oneself. Where one is known and knows, has ties to life and is happy to be tied. I do not call that Kent!'

'The barracks, then, perhaps?' knowing the answer, but posing the question, just the same. She shook her head; one resolute shake; sharp, definitive beyond argument.

'No.'

'So you call nowhere home?'

'Nowhere.'

'You asked if you were alive. What was your meaning in asking me that?' Isabel tilted her head to one side and sighed, before dropping her eyes to his highly-polished shoes. She swallowed, the rise and fall of her throat dancing visibly in her slender, golden neck.

'I do not feel - that is - am I - I know I am alive, for surely I could not contemplate such a proposition if I were not. "I think, therefore I am."', she added with a wry smile, before her face smoothed again and her lips tugged downwards. 'No; I know myself to be alive, but -' She hesitated. Her subsequent words could not be met by anything but alarm, and to speak them to a doctor! What must he think in reply?

'But?' asked the doctor in question, leaning forward in his chair. The leather beneath him creaked with a fervent expectation; he held his breath and waited. This was the crux of her malady; the root cause of her silence. He felt it; he knew it to be so, intrinsically, not merely professionally. 'But, Isabel?' He did not blink as he looked upon her, his steady gaze commanding her to speak; daring her to refuse him. She was obedient if anything, and the uneasy knowledge that she would speak made her heart thrum in her chest. She licked her lips anxiously. Her eyes widened in alarm, and he saw a trace of fear as her lips parted in speech.

'Is this real? This world around me? I know myself to be real, but the places, the people? I feel detached. I feel no connection to anyone or anything. I could almost say is it a dream; that I fell into a coma and am now dreaming; that this world before me is a construct of my own mind.' Dr Lyndhurst smiled at her compassionately.

'Of course it is a construct of your own mind!' cried he, throwing himself back against the upright of his chair. 'We all of us live within our own minds.' She frowned at him, not knowing if he was in jest or in earnest, and he understood her confusion. 'Allow me to explain a moment,' said he, holding up one patient finger. 'You quote me Descartes; now are you fond of Plato?'

'Who is not, that thinks?' came her ready answer; a genuine smile, a spark of fleeting interest. Not acknowledging this flicker of improvement, Dr Lyndhurst nodded succinctly and continued.

'Then what of his allegory of the cave? Are not we all but shadows, dancing upon the wall? The fire burns behind us, warming our backs. We sit - bound in chains - and see nothing of one another but the shadows as they are cast about and bounce upon that domed and sloping prison. We think the shadows to be true; we think that the sight of another human being; we make it our reality, but it is not. Beyond that cave - out there, in the sunlight - is our true existence. Now, cast off those shackles, rise from our knees and step out from the cave into blinding sunlight. Tell me, what do you see?'

'I am blinded, obviously,' replied Isabel. 'I cannot see a thing, having always lived in darkness. I should blink a thousand times or more, but should not see a thing. With time I would gain vision, and I would learn the kiss of cool winds upon my skin. I would sense new smells and see the world I had never learned to see, but I should not know it; I would not understand it, and I could learn of it from no one, because I would not understand the concept of another. Were I to meet a human being, I would know not how to converse with it; I should not recognise its look or dress. How could I learn from it before I had learnt of it?'

'And so?' smiled the doctor.

'And so,' frowned Isabel, thinking deeply, 'and so, I would learn of that new world relying on my own senses; sight and sound and touch and smell. I should not think to lick things; I choose to omit taste!' Dr Lyndhurst laughed, but she chose to ignore him in her determination to continue. 'I should learn of this new world, then, by applying my own capacity for thought, but it would be tainted by my blighted - misguided - existence, in the dark and gloomy cave, and so I should not see the world as those who have always know it. I would find wonder in sunlight, which they would take for granted. I should be fearful of company, where they - being unchained and free to move at will; at liberty to socialise - may feel a wish for solitude. We would co-exist, and, after learning to converse and supposing to understand one another, we would look upon the same object or event and see and feel it differently.'

'Exactly. Indeed!' cried Dr Lyndhurst, in a loud, excited voice; his hands clapped briskly together as though some great feat had been achieved. 'I shall be blunt and name you the cave dweller; I - of course - live only in the sun - and so it is, that when you emerge from that darkness, and we find we reside together - much as we do now - for you have emerged from that darkness - you did some four months ago - look now; we speak, we see and hear, and yet you feel none of this is real; that it exists only in your mind. I tell you, I believe you might be right. It is all interpreted in the mind. The mind makes the banal fantastical. We must allow it, or life should be very dull. I do not think you ill for questioning the foundation of the world around you. I think you ill for refusing to embrace the mind and allow yourself a realty of your own choosing.'

'Oh!' frowned she. He spoke in riddles. Isabel found herself doubting that he was not the one in need of a doctor. 'You mean to tell me that I ought to dream up my own world; a reality of my own design, where I have my own recipe for happiness?' He smiled, but spoke no word of reply. 'I do not hallucinate! You are speaking of hallucinations. No good doctor would suppose that I ought to encourage such a thing; to embrace it, should one arise?'

'A hallucination? No!' cried he, shaking his head in irritation. 'I suggested no such thing. I suggested using your senses; using logic, and taking the information you have received and interpreting that to your own design. That, is no hallucination.'

'Any sense? I can use any sense?' He smiled and nodded. 'Must I use them all?' His eyes narrowed hesitantly, and he drew in a cautious breath.

'You would do well to use all to your advantage.'

'Yes, but what if I should place one sense above another? What if I would indulge the remaining only through the mind; neglect the nose itself, but imagine the smell; taste it in my mind?' Dr Lyndhurst frowned and pursed his lips, blinking rapidly.

'Why ever could not you just breathe in and smell like any human does?' He frowned again and shook his head. 'Unless you were to read a book,' he chuckled, 'then - of course - your knowledge of your environment or company would have to be imagined. Surely, you would see it with your eyes - the words on the page - you might even hear the voices in your head as your eyes scan over the words.' He tilted his head from side to side in a "so-so" gesture, 'you might even smell the rose in Shakespeare's sonnets, but I think it would take a very fine mind to learn all it needs to know from a book. One needs to live to truly know a place or person. We can only suppose from a book. Indeed, leap into a book and I think it almost certain that you would find yourself disappointed.'

'Are you a doctor of medicine or a doctor of philosophy?' asked Isabel, sceptically. 'Leap into a book! What nonsense! A novel - a work of fiction - is just that; fiction! The very opposite of reality.'

'But is it? If someone wrote it, someone thought it, and did not Descartes tell us "I think, therefore I am"? If you accept that - as you asserted that you did, surely you must allow that "I think, therefore it is"? I certainly must; I am an anti-realist.'

'Well, you have certainly coaxed me into speaking to you, but I fear our conversation has been to very little purpose,' Isabel announced, rising from her chair. 'And oh! now we are out of time. Until next week,' smiled she - tight-lipped. In truth, she felt entirely off-kilter - even more so than usual - and she was not sure she wished to see Dr Lyndhurst again; not if he was going to speak nonsense to her and trick her into doing the same in return.

'Next week? I think not. You ought to visit somewhere else - a change of scene. You must be fond of travelling? Take a trip; see if you can find a place to call home. Come back to me once you've found it; I think it the key to your problems, Isabel.' He stood and held out his hand in farewell; not something he usually did, but he hoped not to see his patient for some time to come.

What a strange man, thought Isabel, as she cycled home. She had always thought Dr Lyndhurst quite the enigma. She felt sure he could be no more than five years her senior, but she knew herself to look quite young for her age, so it was possible he did, too. Supposing him to be in his early thirties - as she had predicted - she thought him in possession of a certain gravitas one did not usually find in a man so young. That severity - that quiet dignity - had always unsettled her and made her feel judged, so she had chosen to remain silent; not to confide in him. But then, today, thought she, he was so very different. Talking of the classics, like I had not done since school! She momentarily wondered if he knew more about her than he ought to, for - unusual as it was - philosophy had been a passion of hers since she was but sixteen. She was often mocked for burying herself in some great tome whilst the men about her drank and jeered, but she was a thinker; quiet, internalising - she had always found solace in a book instead of in people.

A book! she thought, padlocking her velocipede to the railings outside her small apartment. All that nonsense about delving inside a book! But, nonsense as it surely was, she could not help but smile at the thought. The curl about her lips stayed in place as she climbed all three flights of stairs; as she jammed her rusty door key into the gnarly old lock, and as she crossed the threshold into her cramped, musty apartment. In truth, it was a bedsit. A sink and stove, one cupboard and a drawer, were all that formed the kitchen. She had the tiniest of fridges and a kettle, but it had a tendency to leak. Her bed was nothing more than a futon - which doubled as her sofa - and her bathroom floor was obscured entirely by the presence of one solitary bath mat. It is only temporary, she told herself with resignation - as she did each time she returned to the place she nominally called "home". As soon as I am well, I will return to the barracks, but, on thinking this - unlike on other days - she was stopped short. Her pace stilled mid-stride. She blinked into the gloomy room as particles of dust and fluff tumbled in the air, and she dipped her brows in thought. Do I want to go back there? In truth, she did not. Or rather, she knew it - had known it - but could never admit to such a thing; not until now. A book, she smiled again. If only it was that easy. She sighed, filled a bowl with cereal, and sat upon her futon, spoon in hand. Any book? thought she, spoon hovering about her parted lips. Wizards and other mystical creatures danced before her eyes as she mulled her options over, but she quickly discounted them, for how on earth could she ever use her senses to come to know a talking tree? Fiction! thought she. A reality? How absurd!

Absurd as it may be, Isabel did spend the rest of the evening thinking upon Dr Lyndhurst's words. She would take a trip from Kent; the county held nothing for her, and she had thought - since leaving the barracks - that she might like to return to Oxford. Her memories of the place were sparse, but she felt that if anywhere were to strike her as "home", Oxford - as her birth place - was a fair place to start. This determined, she packed a bag with a small ration of clothing, an anthology of works by her favourite author - Gaskell - and a solar charger for her phone, leaving the plug-in behind. She was accustomed to traveling with little in the way of possessions, and seldom took anything that she did not deem essential, but into her bag she placed her metal tin - an old army munitions box she'd found at Enfield Pageant in amongst the Autojumble, some seven or so years ago. The box, she did not open, for the treasures inside brought only pain, but she was loath to part with something so very personal, and so could not bear to leave it behind, if she was to be from Kent for any prolonged duration. Yes, thought Isabel, I shall catch the train to London - then on to Oxford - and see if I can find a place to call home. And then - because she held little hope of achieving such a long-held aim - she sank back into her futon and pondered if there was any book she felt could hold for her a world more tolerable. She thought immediately of Gaskell's "dirty, smoky" Milton, and smiled. She could almost taste the soot from the smokestacks on her tongue, and she had not had to lick a thing! She smiled to herself in the darkness of the room. Horrible place, she said to herself, but Mr Thornton; surely a woman would put up with any place on Earth - make any sacrifice - to be with a man such as he?