Artwork by Anna Repp

As so much of Charles Darwin's correspondence has already been published, it is a rare event to discover a previously unknown letter from him, especially one concerning his seminal work, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life. By kind permission of the letter's owner and the esteemed editor of this magazine, I am pleased to be able to reprint the letter here, and I will restrict myself to the minimum of prefatory remarks necessary to give context to this intriguing document.

The first edition of the Origin of Species, as it is now more commonly called, was published in November 1859. Darwin finished correcting the proofs of the book on 1 October, and on the following day he set out for the Yorkshire town of Ilkley, where he spent two months undertaking the "water cure" that was so popular during the Victorian era.

It appears to have done him little good, for in his extant correspondence we find him writing, "I have had a series of calamities: first a fall culminating in a sprained ankle, and then a badly swollen leg and face, followed by itching rash and a frightful succession of boils -- a dozen at once. I cannot now walk a step, owing to a hideous boil on my knee. We have been here six weeks, and I feel worse than when I came."

The newly discovered letter dates from soon after Darwin's arrival in Ilkley, prior to the aforementioned sequence of calamities -- which might almost be viewed as a Biblical judgement upon him: after his Fall, a Plague of Boils. The addressee, William Darwin Fox, was Darwin's second cousin and a lifelong friend; they studied theology together at Christ's College, Cambridge, and in 1859 Fox was Rector of Delamere, in Cheshire. Darwin himself originally intended to become a clergyman.

In the transcription below, the letter's spelling and punctuation have been regularised for reading convenience. Some text has been inferred where Darwin employs abbreviations, or where his handwriting approaches illegibility.

As to the provenance and authenticity of the letter, I am personally acquainted with the letter's owner, who wishes to remain anonymous. I trust her absolutely as a scholar and a lady; therefore I take the veracity of the letter on faith. However, I am informed that scientists are currently analysing the manuscript, and their conclusions will be announced soon. In the event of any doubts arising, readers may judge for themselves what to believe.

Ilkley Wells House, Otley Yorkshire

13 October 1859

My dear Fox,

I arrived at the Hydropathic Establishment last week, and your note has just reached me. I grieve to hear, or rather infer, that your condition has not improved. I hope you will come here if your duties permit. Dr. Smith, although a Homoeopathist, is otherwise sensible and very methodical in bad illness, even if he has the air of caring much for the Fee and little for the patient. There is a capitally efficient steward, and the House seems well managed.

It is a curious life here: we sit down 50 or 60 to our meals, and in the evening there is either singing or acting (which they do formidably), or cards et cetera. I get on very comfortably and idly -- the newspaper, a little novel-reading, the Baths and loitering kills the day in a very wholesome manner. Did you ever hear of the American game of Billiards? There are some splendid players here who often make breaks of 30 and 40. I shall miss the Billiard Table when I leave here.

I had wanted to forget my weariful book on Species for a while, but not long after I arrived, something happened which quite put my thoughts in a fluster.

Here at the Establishment we meet many people, fellow sufferers all, and I had been introduced to a Mrs. Danzig who stoically endures fearful attacks of dropsy. Her niece lives in one of the farms along the edge of the Moor, and last Friday the girl -- Annette -- arrived here and rather insisted on speaking with me. Her manner was shrill, and one hesitates to interrupt one's Billiards when feeling relaxed after purging, but I at last consented when I perceived she would not relent.

"Mr. Darwin, my aunt tells me that you are a most eminent naturalist. You have travelled all around the world and seen every creature that God has made."

She spoke the latter phrase -- "God has made" -- in the manner of a commonplace expression, rather than in the reverential tone that you, my old Fox, might use in a sermon. I am compelled to notice the particular ways in which people speak of Religion, as it so often affects how they comprehend my Theory. (Indeed, I find that my Theory affects how I comprehend Religion, as I shall relate.) The girl's comportment suggested that in reaching perhaps nineteen years of age, she had received only rudimentary education -- as is, alas, all too common among her class.

"I have indeed travelled far, Miss Annette," I said, "but I would not claim to have seen every creature that lives on the Earth, nor indeed in England."

"But you have books, don't you? You would know whether a creature was something extraordinary?"

I said, "I'm acquainted with the broad kinds of plants and animals that natural science has so far discovered. Do I understand that you have seen a rare creature?"

"I've not only seen it, I've captured it!"

Country folk are familiar with the wildlife of fields and woods. Since the girl lived on a farm, I puzzled to think what she might have captured that she would not recognise. Perhaps it had escaped from some private menagerie.

"What does it look like?" I asked.

"It looks like . . ." She paused inordinately, then just as I was about to speak, she blurted out, "I do not say it is, sir -- I only say what it looks like. But it looks like a fairy!"

I returned an equally long pause. I had not expected such an answer. At last I said, "In what way does it look like a fairy?"

"It has wings!" she exclaimed.

"Are you sure it isn't some sort of bird? Perhaps you are unaware that parrots can be trained to talk."

She shook her head, and muttered something that might almost have been an oath. "I can recognise a magpie from a mouse. It's not a bird at all. Be it ever so small, it has the face of man, except with a greenish cast."

On this, I naturally suspected some poor human wretch, perhaps with chlorosis and a hunched deformity that could be mistaken for wings.

"You would be better calling for a doctor."

The girl gave me such a look as I have not received for many a year. It took me back to our time at Cambridge -- my dear Fox, do you remember those days we chased after beetles! -- when the tutors frowned with desiccated contempt at our more otiose utterings. Yet here I was at 50, as old as a senior Don, being patronised by a girl the age of a student, looking at me as if I'd ludicrously confused the Homoousion and Homoiousion creeds.

"I live on a farm," she said. "I wouldn't call a doctor to the lambs or the swine, and I wouldn't call him to this. Neither would I call a veterinarian! I tell you, sir, the creature is unprecedented."

Clearly, nothing would do but that I examine it. "Can you bring it here, or must I travel?"

"It's in our barn, if you could come and look. 'Tisn't far -- just a couple of miles."

Ah, the thoughtlessness of youth! Speaking to someone old and grey and ill, she said that "a couple of miles" wasn't very far. Nevertheless, I thought I might manage it. I'd yet seen little of the Yorkshire countryside, and a short excursion might be pleasant and indeed restorative. Too, of course, I was curious to see the creature of which she spoke. We arranged that on the following day, Sunday morning, I would visit her farm and see whatever lay within.

That evening, I spoke to some of the staff at the House and asked about any local stories of fairies. I learned of a purported sighting at another hydropathic establishment: the White Wells spa, higher on the Moor. In 1820, before the bath houses were roofed over, the attendant (one William Butterfield) arrived early to open up the doors, but the key merely turned round and round in the lock. After forcing the door open, he found to his astonishment a group of fairies frolicking by the water. They were tiny figures, all dressed in green. When he surprised them, they disappeared over the wall and into the heather.

Natural science deals in specimens rather than anecdotes. I want a creature that you can give to a taxidermist and have stuffed. Yet the girl had promised to show me such a one, and if it did exist, then the earlier stories would imply that fairies had lived on the Moor for some time. Indeed, since such tales stretch as far back as human history -- as far back as revealed Religion -- then the fairy race must have lived for as long as Man.

But what kind of creature is a fairy? That night, after I retired to my room and blew out the candle, I shifted restlessly in my bed, unable to sleep for pondering the question.

My theory of natural selection requires that life proceeds by common descent. All creatures are related, however distantly. So any particular creature must possess living relatives, of some kind; and ancestral forms should be preserved as fossils. Any beast, however unprecedented to man's eyes, must fit somewhere within the Linnaean taxonomy.

If fairies exist as material creatures, what genus do they occupy? Where are their fossils? (The fossiliferous strata contain an imperfect sample of past organisms, yet surely we could hope for one example to be retained from the entire fairy lineage.) If the traditional description be correct -- like a small man with wings -- it is clear that fairies cannot fit anywhere within the existing genera of Mammalia. We could only accommodate them within Animalia by supposing an entirely separate line of descent, one which has left no close relatives, no intermediate forms, and no fossils. The evidence does not support it.

It would be simpler, therefore, to suppose that fairies were a separate creation. After all, why should we require all creatures to be related?

We indeed require it, for if we allow that any creature may be a separate creation, then we must allow the possibility to all creatures. How could I argue that a wolf must have descended from canid predecessors, if I cannot argue likewise for a fairy? Any opponent could simply say, "The wolf was independently created in its current form, just like a fairy." I would have no refutation for such a critique. Even those who accepted the Wolf might balk at the descent of Man from simpler progenitors, if given the excuse of the Fairy.

My hypothesis must explain all creatures, or it explains none. Everything, or nothing. The thought burned in my mind: If this fairy truly exists, it will destroy my whole Theory. I could sleep only briefly, and kept waking in turmoil. In my dreams, I walked restlessly in a huge library, with a green figure fluttering bat-like above me; and wherever it brushed the shelves, the books crumbled to dust.

If the creature should prove authentic, I would have to write to Murray and ask him to halt publication of Origin. All my work wasted, the labour of twenty years overthrown by a single specimen from a Yorkshire farmyard.

You may smile at my fears that a fairy could exist. Yet seeing such a specimen might be my punishment for the sin of pride. If I profess to know the Origin of Species, might not God rebuke my presumption by sending a creature that my Theory cannot explain?

I tried to comfort myself by reflecting that the creature would most probably be something commonplace, or at least explicable. I grew happier for a few moments, until I realised that I had fallen into a far worse cast of mind.

No true philosopher fears the evidence. Does any naturalist ever wish not to discover a rare specimen?

If I could authenticate a Fairy, that would be an achievement as great as the discovery of innumerable species in the Antipodes. The perplexity of folklore would be resolved. Our knowledge of Nature would still advance, albeit in another direction -- away from my cherished Theory.

And if the Fairies were established to be a separate race, then this would show the direct handiwork of the Lord. Our most eminent divines would speculate upon their spiritual status: they might even be considered as an Unfallen race, living in harmonious relations with nature, in contrast to Man. "And unto Adam he said, Because thou hast hearkened unto the voice of thy wife, and hast eaten of the tree . . . cursed is the ground for thy sake; in sorrow shalt thou eat of it all the days of thy life; Thorns also and thistles shall it bring forth to thee; and thou shalt eat the herb of the field; In the sweat of thy face shalt thou eat bread . . ." Yet we see that Fairies do not plough nor reap; they are reported to dance far more than they labour.

The direct handiwork of the Lord, I wrote. No doubt many people -- including you, old Fox -- would find nothing surprising or untoward in that. It is a greater challenge for me. Over many years, and particularly as I became convinced that Man descended not from a recent Garden but from a much older lineage, I have grown to doubt the visible handiwork of God. And from there, it is but a short step to (as I hardly dare write) doubting God. I have not yet taken that step, but it is constantly in mind: a precipice upon which I stand, looking out into a vast void . . .

In writing this, I rely on your strictest confidence. I would never express such sentiments in public. Any merit in one's theories is easily overlooked if opponents can attack ad hominem on the grounds of unorthodox belief. I am hardly alone in such discretion. For instance, Lyell is firmly convinced that in his Principles of Geology, he has weakened faith in the Deluge far more efficiently by never having said a word against the Bible, than if he had acted otherwise.

And, too, I know how deeply it would distress my wife if I proclaimed myself an Atheist. Emma remains fervently devout. She is aware that my reflections have caused me to reject the literal interpretation of Genesis, but she does not (yet) suspect how far my doubt has carried me, and how much further it may lead.

She fears for the state of my soul. I know that she prays for me.

If evidence of God's handiwork impelled me to renounce doubt and wholeheartedly accept Christian Doctrine, then Emma would rejoice. She would be as relieved from worry as if she'd seen me saved from a sinking ship. At present, she pictures me floundering in the water, flailing further and further from land, imminently drowning yet wilfully refusing the lifeboat offered by the Church.

And so I knew that if this Fairy proved authentic, then I should be reconciled to the Christian Faith and my wife would be so happy as to weep with it.

When something momentous is at hand, it is natural to prefer one outcome over another. Tomorrow I would discover what kind of creature lay within Annette's barn. Either my theory would stand, or my soul would be saved.

Yet I could not decide which result I most desired. I would settle upon the first, and feel guilty about Emma's anguish; then I would opt for the second, and regret my twenty years of lost labour.

The dilemma grew so sharp that I even thought of offering up a prayer, begging the strength to deal with either outcome. But I did not; I own that it has been some time since I had the habit of prayer. As to the issue confronting me, I felt I should be guided by the evidence at hand -- not by a prompting that I could never be sure was the Lord's answer rather than my own base and selfish wish.

It shouldn't matter what kind of wishes -- if any -- filled my heart when I examined the creature. Yet our desires and preconceptions may shape what we see, and what we conclude. All geologists see the same Earth, but some infer a swift Flood while others deduce slow changes over immense time.

I spent such a restless night that my aches magnified themselves, undoing all benefit from the Hydropathy, and the following morning I broke fast in a state of ill humour quite unlike my usual anticipation before field excursions.

When Annette arrived, I was surprised to see that she had come alone. "Perhaps your aunt might prefer that a chaperone accompany us?" I suggested. I was not sure who might serve that role, since Mrs. Danzig looked too ill to undertake country walks.

"I thought you were married, Mr. Darwin."

"I am. It's your reputation I would preserve, unless you are unconcerned about being seen walking away with a stranger."

She laughed it off. "I have no reputation to protect!" Then she gave me a wary glance and said, "I only mean that I'm a farm girl, not a fine lady on an Estate. I assure you I don't take a chaperone when I walk up with the shepherd to help get the sheep in."

Thus rebuked, I pressed no further on the topic, and we set out. As a veteran of many expeditions, I had known to wear my most robust clothes and boots, of which I was soon glad when we turned onto a muddy track at the bottom of the Moor. To our right, cattle and sheep occupied green pastures divided by dry-stone walls stretching down to the River Wharfe. To our left, the moor rose steeply, with crags jutting out between the bracken and bilberry bushes. I had arrived in Ilkley too late in the year to sample the bilberry, which I understand is a northern delicacy. (Perhaps you have it in Cheshire?)

The weather was cold and grey, with a flinty breeze blowing through the valley. Yet as I am so often ill, or working in my study at Down, I relish any chance to get outdoors and look at the landscape. I saw that the edge of the Moor is formed of what they call gritstone, a hard coarse-grained sandstone. How many aeons must it have taken for estuary sandbanks to subside and compress into these rigid rocks! It makes the mind dizzy to contemplate.

I have been told that there is a Roman Road running through the vicinity, and that the moor shows evidence of even earlier occupation, as the Swastika Stone and other carvings are thought to be relics of the illiterate pre-Roman inhabitants of these isles. People have lived here for thousands of years. The area feels ancient -- even the lichen-encrusted stone walls, while merely a few centuries old, contribute to the aura of antiquity hereabouts.

But if we compare the age of Man to the age of the rocks on which he walks, we find a difference of immense magnitude. Geologists cannot yet calculate the relative proportion, but looking at the mile-long track, and imagining it as the age of the Earth, I felt that Man could not account for more than a few steps along the way. Sandstone accretes with imperceptible slowness. Natural selection operates over myriad generations. This is the aspect of my Theory that the public will find hardest to comprehend: the enormous span of time over which species may change.

If God is so concerned with human behaviour that he gives commandments and answers prayers, then what occupied His attention throughout all the aeons before Man arrived upon the Earth?

As if in reproach to my thoughts, church bells began ringing in the town below.

"Will you be attending church later?" I asked Annette, in the spirit of making conversation.

"No, I have to feed the chickens," she said.

We trudged onward, Annette not quite hiding her impatience at my slower pace, and she burst out, "I have to feed the chickens, collect the eggs, milk the cows, muck out the pigs, do the washing . . . It's not easy, you know. We can't all marry a rich husband, like my aunt. I scrape for every penny. Capturing this fairy was like a blessing from Heaven." Again she spoke in the tone of a verbal commonplace, rather than as if receiving an actual gift from the Lord. "What do you think such a prodigy is worth, Mr. Darwin?"

The question did not surprise me. A pure love for natural philosophy is rarely found among folk with immediate practical concerns. "If it's genuine, I'm sure it's worth something," I replied. I would pay her from my own accounts, if necessary. "But I cannot say for sure until I have seen it."

Yet although the question did not surprise me, it somehow disheartened me. Annette's conversation had the air of someone who cared nothing for knowledge, religion, propriety, or aught other than immediate advantage.

I wanted to attribute this to her circumstances. If we complain about the morals of the poor, we should at least consider whether the fault lies in their morality, or in their poverty.

But I had a darker fear. Why does the world have such a horror of Atheism? It must be because our churchmen and most of our philosophers believe that as religion stems from God, so morality stems from Religion. Therefore a world without God is a world without morality -- a world where people care for nothing beyond their own advancement.

When I suggest that the origin of species is not the direct work of God, and when geologists do likewise for the landscape, we are accused of arguing for a world with no morals, no scruples, no higher feelings than base selfishness.

I do not relish the thought of such a world. But I follow wherever the facts may lead.

Our path led into a farmyard, with the usual earthy smell of such places. Chickens clucked nearby, and a grey cat surveyed us with disdainful gaze. The farmhouse appeared old but sound, built from squared-off stone. The shabbier outbuildings had irregular patched-up walls, and roofs bowing under the weight of years.

Somewhere in one of these barns lay the creature that could save us from a Godless, empty world of meaningless strife. All of an instant, the idea struck me that perhaps it wasn't a material creature at all, but something supernatural. Perhaps it was even an angel, albeit a tiny angel.

I only relate these thoughts to illustrate my disordered mind. Many factors had jointly reduced me to this state: working too hard on my Species book, having been forced to rush into publication; my recurring illness; then the strain of the journey North and apprehension over how my book would be received; now the mysterious Fairy and the conflicting sentiments it engendered . . .

Annette pointed to the most distant of the barns. "I have work to be getting on with -- the cows need milking -- so you must examine the creature alone. Mind you don't let it escape!"

I let her depart. If the purported prodigy proved genuine, I would subsequently enquire how it had been captured, whether others had been seen, what habitat and sustenance it favoured, and so forth. If it were a fraud, I would at least have spared myself listening to a lot of lies beforehand.

She hurried to the farmhouse and emerged with a milking pail, the grey cat taking its opportunity to slip inside the kitchen door. I walked across the yard to the indicated building, an ancient hut of ramshackle stone and boarded-up windows. It might once have been a small one-room cottage for farm workers. The original hinged door had gone: the replacement door merely leaned against the outside wall. A swathe of coarse netting hung from nails hammered into the lintel. The net was an incongruous sight so far from the sea, and I wondered what use it had on the farm; perhaps there were fishponds near the river.

I pulled aside the netting to reach the door. Before I entered, I draped the net behind me, ensuring that it blocked the entire doorway, weighting the bottom with a heavy stone. The creature might be ready to rush out, alert for any chance to flee. I slid the door aside.

As my eyes adjusted to the dimness, I distinguished a pile of hay, a stone water-trough, a stack of fence-posts, and many small pellets that looked like the droppings of rats or mice -- or the Fairy.

Nothing stirred. I listened, but heard only distant chimes reverberating up the valley from the town below. The barn smelled old and stale and rotten. I walked carefully across the floor, peering into the shadows behind all the clutter, then up into the sagging rafters and the underside of the slate roof.

A movement! Something emerged from within the rafters. The creature flew so fast, I caught only the barest glimpse. It made not the least sound as it alighted elsewhere in the interior. The faint noise from the valley seemed far, far away. Inside the barn the silence weighed down, as heavily as the sunken roof, and I had a sudden dreamlike dread of being crushed.

I walked across the room toward the creature. When I approached, it took flight once more. It fluttered in front of the doorway, allowing me to estimate its wingspan as about that of a rook, although it had a proportionally larger body relative to the wings. Then it retreated to the dim crannies of the rafters.

I had brought no butterfly-net or the like to Ilkley, not having anticipated any field expeditions, so perhaps it was no surprise that I hadn't thought to bring anything with me to this barn: not a lamp, nor a net, nor aught useful. But I berated myself nonetheless. I realised that I'd pre-judged the issue: I'd brought nothing that a naturalist might normally carry, because I had not expected to see anything. After twenty years of working on my Theory, I had become so convinced of its correctness that I assumed no contrary example could possibly exist.

Rather as a writer on Natural Theology can point to any worldly phenomenon and find ways of relating it to God, I had -- in opposite fashion -- begun to see everything as only worldly, relating only to other creatures. I had fallen into a trap of false thinking. No: in becoming aware of it, I hadn't yet wholly succumbed. But I was falling . . .

A wave of dizziness swept over me. As the daylight outside grew brighter -- the sun having come out -- so the interior of the hut became darker by contrast, full of shadows. A thought struck me that it would be simple to let the creature escape, thus avoiding the revelation of what it might be, and what it might imply. The temptation seemed to hang in the air before me, needing but a single step to reach out and grasp.

No true philosopher fears the evidence.

I resolved to look without prejudice and discover the truth, whatever it proved to be. I grasped a spare corner of the netting. Then I threw up a handful of hay and shouted, "Reveal yourself, whatever you are!" I calculated that the noise and disturbance would provoke the creature to attempt escape. If I acted swiftly enough, I could wrap it in the net and thereby capture it.

The creature indeed emerged and flew toward the doorway. I swiftly pulled the net around, closing in on the wildly fluttering form. It struggled so much that I obtained no clear view of its structure, save that it appeared to be bipedal with owl-like wings. I thought I glimpsed a visage at first stark and stern, and then a moment later resembling the old marble statues of saints worn smooth and blank by the passage of years and the rubbing of numberless hands. My mind surged with excitement at the prospect of such an intriguing specimen to examine. Soon, very soon, I would see the truth.

Yet as I closed the net tighter, the captive's wings shrank away. As I leant inward for better examination, I found I could not discern the creature's face. The closer I looked, the less I saw. Before my astounded gaze, the creature vanished.

Rather than "vanished", I could write that the creature "shrivelled" (if I credited a subjective impression), or "dissolved" (if I conjured a fanciful metaphor). But the subjective and the fanciful have no place in the sober record of natural science. I write "vanished" as my only definite knowledge is this: one moment, the creature was caught in the net; the next, it had utterly disappeared.

I examined the netting, expecting to find a previously unnoticed slit in the mesh. But I could discover no fissure large enough to permit escape. And, indeed, I'd not seen anything fly away.

If it had escaped unseen into the open air, the creature was beyond retrieval. But if it yet lurked somewhere within the barn, then perhaps it could be recaptured. Again I searched the shadowy interior. The silence was increasingly oppressive, all reverberation from the valley having ceased. The church bells had stopped ringing.

My initial inspection found nothing. I would have continued searching, but Annette returned. "Have you finished in there?" she called. "What do you think it's worth?"

"It's gone, I'm afraid," I said.

"Gone?" She trembled with indignation, and I could see that if I were a small boy, I would have received a fearsome slap across the face. "How can it have gone? I told you to be careful!"

"It must have wriggled through the net."

As I spoke, I was aware how inadequate this sounded. If it had escaped through the netting, it could have done so at any previous time, since the leaning door had never impermeably obscured the whole doorway. I felt strongly, if unreasonably, that the creature's disappearance stemmed more from my scrutiny than any other factor. Yet I could not defend this as a logically robust proposition, and it certainly wouldn't satisfy Annette.

"I'm sorry. The creature disappeared in my possession, so I shall compensate you."

"Indeed, sir, I think you must!"

I will spare you an account of the distasteful haggling that followed. As soon as I could decently manage, I departed and began walking back. But I was so perturbed by what had happened, and so occupied in turning it over in my mind, that I neglected to pay sufficient attention to the road. I tripped upon an unseen obstacle and sprained my ankle.

You can well imagine my mood when I finally returned to the Establishment. My ankle ached abominably. I seethed with frustration at not having examined the purported Fairy, leaving me only with fruitless questions.

Foremost, I could doubt whether I'd genuinely seen anything unusual. My views of the creature had been fleeting. It had previously been described to me as a Fairy, perhaps inspiring a predisposition to interpret glimpses in such a manner. We so often see what we expect to see.

Yet that answer, however comforting, did not adequately explain all aspects -- for if the creature had never been extraordinary, then why would Annette have asked me to come and see it?

I might suspect some larcenous scheme (since Annette had indeed succeeded in extracting payment from me), but I couldn't fathom its operation. Annette was not nearby at any time when I saw the creature, or when it disappeared. I could only impute her involvement by fancifully allowing her a supernatural faculty of summoning and dismissing Fairies. Yet such an assumption is an excessive contrivance. We have long abandoned the primitive practice of ascribing strangeness and misfortune to witchery, and I do not propose to revive it. (Even our clergymen often disdain the notion of witchcraft, although if witchery is the Devil's work, it is therefore surely also evidence of God.)

No, on reflection I believe the most likely answer is that the creature was simply an exotic bird, escaped from some rich man's aviary, and it squeezed through the net too swiftly for my gaze to follow.

I firmly believe that nothing can remain mysterious when approached with a keen truth-seeking eye. Our knowledge advances slowly but inexorably, banishing the fanciful and inexplicable.

To ascribe anything to supernatural creatures, or to witchery, or to the hand of God, is merely to confess our ignorance. Whatsoever puzzles us today, we may solve tomorrow. The more we currently attribute to God, the more He must inevitably diminish.

Perhaps when Thunder and Lightning were first explained from secondary causes, some folk regretted to give up the idea that each flash was caused by the direct hand of God.

I shall write no further on this, for I know I will not convince you. I have only written at such length to clarify my own thoughts.

In consequence of the creature's disappearance, no extant specimen contradicts my hypothesis, and so my book may proceed. I confess to feeling considerably relieved, as it would have caused much trouble to cancel at this late date, but you can be sure I would have done it, given sufficient cause.

I have asked Murray to send you a copy. I know you will disagree with my Theory and its corollaries. I have resigned myself to my wife's distress, and yours too. For Emma's sake I shall remain discreet in my opinion of Natural Theology, but I will not recant it -- not until I see evidence that stands firm, rather than evaporating upon examination.

Most affectionately yours,

Charles Darwin

PS: Yet if my scrutiny dispelled the supernatural, was that my reward for seeking the certitude of worldly evidence -- or was it my penalty for being doubtful as to anything beyond?