Inception of Darwin's theory
The inception of Darwin's theory occurred during an intensively busy period which began when Charles Darwin returned from the survey voyage of the Beagle, with his reputation as a fossil collector and geologist already established. He was given an allowance from his father to become a gentleman naturalist rather than a clergyman, and his first tasks were to find suitable experts to describe his collections, write out his Journal and Remarks, and present papers on his findings to the Geological Society of London.
At Darwin's geological début, the anatomist Richard Owen's reports on the fossils showed that extinct species were related to current species in the same locality, and the ornithologist John Gould showed that bird specimens from the Galápagos Islands were of distinct species related to places, not just varieties. These points convinced Darwin that transmutation of species must be occurring, and in his Red Notebook he jotted down his first evolutionary ideas. He began specific transmutation notebooks with speculations on variation in offspring "to adapt & alter the race to changing world", and sketched an "irregularly branched" genealogical branching of a single evolutionary tree.
Animal observations of an orangutan at the zoo showed how human its expressions looked, confirming his thoughts from the Beagle voyage that there was little gulf between man and animals. He investigated animal breeding and found parallels to nature removing runts and keeping the fit, with farmers deliberately selecting breeding animals so that through "a thousand intermediate forms" their descendants were significantly changed. His speculations on instincts and mental traits suggested habits, beliefs and facial expressions having evolved, and considered the social implications. While this was his "prime hobby", he was struggling with an immense workload and began suffering from his illness. Having taken a break from work, his thoughts of marriage turned to his cousin Emma Wedgwood.
Reading about Malthus and natural law led him to apply to his search the Malthusian logic of social thinking of struggle for survival with no handouts, and he "had at last got a theory by which to work". He proposed to Emma and was accepted. In his theory, he compared breeders selecting traits to natural selection from variants thrown up by "chance", and continued to look to the countryside for supporting information. On 24 January 1839 he was elected as Fellow of the Royal Society, and on the 29th married Emma. The development of Darwin's theory followed.
Transmutation[edit]
Context[edit]
Darwin was concerned to make sure that his theorising, whether published or private, fully complied with the accepted scientific methodology of his peers. In the scientific societies and at informal dinners he discussed methods with two leading authorities on the topic, John Herschel and William Whewell.[15]
Scientific circles were buzzing with ideas of natural theology. In a letter to Lyell, Herschel had written of "that mystery of mysteries, the replacement of extinct species by others". This was circulated and widely discussed, with scientists sharing Herschel's approach of looking for an answer through laws of nature and rejecting ad hoc miracles as an explanation.[16] Charles Babbage expressed in his Ninth Bridgewater Treatise (1837) a view of "Nature's God" along the lines of a programmer of such laws.[17]
Darwin's freethinking brother Erasmus was part of this Whig circle and a close friend of the writer Harriet Martineau, who promoted the Malthusianism underlying the controversial Whig Poor Law reforms (1834) to stop welfare from causing overpopulation and more poverty, which were then being implemented piecemeal in the face of opposition to the new poorhouses. As a Unitarian, Martineau welcomed the radical implications of transmutation of species, which was promoted by Grant and some medical men but anathema to Darwin's Anglican friends who saw it as a threat to the social order. Transmutation threatened the essential distinction between man and beast, and implied progressive improvement with the implication that the lower orders could aspire to the privileges of their aristocratic overlords.[18]
The medical establishment controlling the London teaching hospitals, including the Royal College of Surgeons, was restricted to Anglicans and dominated by the aristocracy who saw perfect animal design as proof of a natural theology supporting their ideas of God-given rank and privilege. Since the 1820s large numbers of private medical schools joined by the new London University had introduced the "philosophical anatomy" of Geoffroy Saint-Hilaire based on unity of plan compatible with the transmutation of species, implying ideas of progressive improvement and supporting radical demands for democracy. This anatomy had already spread from Paris to the medical schools of Edinburgh, and the new London schools attracted Scots, including Grant. Numerous journals now promoted these radical ideas, including Thomas Wakley's The Lancet (started in 1823 with support from William Cobbett and William Lawrence, whose 1819 publication of evolutionary ideas the Crown had prosecuted for blasphemy). In response, the medical establishment gave support to the idealist biology of Joseph Henry Green (1791–1863) and of his younger protégé Richard Owen (1804–1892), based on the vitalism of German Naturphilosophie and Platonic idealism, which saw anatomical forms as "archetypes" in the Divine mind, imposed through "descensive" powers of delegation of divine authority in accordance with traditional hierarchies.[19]
Red Notebook[edit]
In 1836 Darwin used his Red Notebook to record field observations during the last stages of his Beagle voyage, from May to 25 September. Page 113 mentions a meeting with Richard Owen, after the ship's return to England in October. Later notes mention discussions with other experts, including the geographer Sir Woodbine Parish, geologists Charles Lyell and Roderick Murchison, and the conchologist James De Carle Sowerby. Darwin also took brief notes on what he was reading, reminders on planned publications including his Journal of the voyage, and his developing "theories", "conjectures", and "hypotheses". He continued using the notebook until May or June 1837.[20]
In his later "Journal", Darwin recalled having been "greatly struck from about month of previous March on character of S. American fossils – & species on Galapagos Archipelago. – These facts origin (especially latter) of all my views."[21]
His first reference to transmutation appears in the Red Notebook around early March 1837, after John Gould told him that the common Rhea was a different species to the Petisse. Darwin wrote "Speculate on neutral ground of 2 ostriches; bigger one encroaches on smaller. change not progressif<e>: produced at one blow. if one species altered", proposing a sudden change or saltation in contrast to Lamarck's idea that species graded imperceptibly into each other: later, Darwin referred to this jump as inosculation. He drew on the relationship Owen had shown between fossils of the extinct giant Macrauchenia and the modern guanacos that Darwin had hunted in Patagonia: "The same kind of relation that common ostrich bears to [Petisse]: extinct Guanaco to recent: in former case position, in latter time. .... – As in first cases distinct species inosculate, so must we believe ancient ones: not gradual change or degeneration. from circumstances: if one species does change into another it must be per saltum – or species may perish." Here, he related the geographical distribution of species to their replacement over time, and tentatively proposed that the Rheas had a shared ancestor.[22]
He noted his thoughts on reproduction and extinction; "Tempted to believe animals created for a definite time: – not extinguished by change of circumstances", and various domesticated animals had "all run wild & bred. no doubt with perfect success. – showing non-Creation does not bear upon solely adaptation of animals. – extinction in same manner may not depend. – There is no more wonder in extinction of species than of individual."[22]
Darwin's notes mention several papers based on his geological writings during the voyage.[23]
At the Geographical Society meeting on 3 May 1837, Darwin read his paper on strata around Río de la Plata where he had found fossils including the Toxodon.[24] At the same meeting, announcements were made of the first discoveries of ancient fossil primates; finds by Proby Cautley and Hugh Falconer in Neogene strata of the Sivalik Hills, and by Édouard Lartet in Miocene beds at Sansan, Gers.[25] Later, Lyell joked uncomfortably to his sister that "according to Lamarck's view, there may have been a great many thousand centuries for their tails to wear off, and the transformation to men to take place", but Darwin was beginning to look at these "wonderful" fossils in relation to transmutation.[26]
Darwin's notes mentioned his "Coral Paper" which he had originally drafted in 1835; he presented this on 31 May 1837 at the Geological Society of London, and later used it as the basis for his book on The Structure and Distribution of Coral Reefs.[23]
At their frequent meetings, Owen argued that intrinsic "organising energy" in the "embryonic germ" set the lifespan of the species and precluded transmutation. The botanist Robert Brown showed Darwin a different concept, of "swarming atoms" inside the germ, allowing nature's self-development. Embarrassed by his lack of labels for his finch specimens, he examined FitzRoy's in the British Museum and contacted seamen including Syms Covington for their collections. From this he was able to relate the finches to separate islands, with distinct species on each island. As well as pressing on with his Journal, he started an ambitious project to get the expert reports on his collection published as a multi-volume Zoology of the Voyage of H.M.S. Beagle. A search for sponsorship was answered when Henslow used his contacts with the Chancellor of the Exchequer Thomas Spring Rice to arrange a Treasury grant of £1,000,[27] a sum equivalent to about £115,000 in present-day terms.[28]
During the Beagle voyage Darwin had noted the distribution of the two species of Galápagos iguanas and suspected that "this genus, the species of which are so well adapted to their respective localities, is peculiar to this group of Isds". He had identified the sea iguanas from a book on board as having been named Amblyrhyncus Cristatus by Bell from a specimen which had arrived in Mexico, probably found on the Pacific shore.[29] In June he gave this information to William Buckland.[30] As the Victorian era began, Darwin pressed on with writing his Journal, and in August 1837 began correcting printer's proofs.[31]
Thoughts of marriage[edit]
The Hensleigh Wedgwoods were now living next door to Erasmus. In early June 1838 they were visited for a week by Catherine Darwin and Emma Wedgwood, returning from a family get-together in Paris. As Emma told her aunt a few weeks later, "Charles used to come from next door, so we were a very pleasant, merry party."
Illness prompted Darwin to take a break from the pressure of work: on 15 June he told his cousin William Darwin Fox; "I have not been very well of late, which has suddenly determined me to leave London earlier than I had anticipated. I go by the steam-packet to Edinburgh. – take a solitary walk on Salisbury crags & call up old thoughts of former times then go on to Glasgow & the great valley of Inverness, – near which I intend stopping a week to geologise the parallel roads of Glen Roy, – thence to Shrewsbury, Maer for one day, & London for smoke, ill health & hard work."[66] On 23 June 1838 he took the steamboat to Edinburgh to go "geologising" in Scotland. After revisiting Edinburgh on 28 June (the day that Queen Victoria had her coronation in London) he went on to Fort William. At Glen Roy in glorious weather he was convinced that he had solved the riddle of the "parallel roads" around the glen, which he identified as raised beaches, though later geologists would support the ideas of Louis Agassiz that these had been formed by glaciation.
Fully recuperated and optimistic, he returned home to The Mount, Shrewsbury. He discussed his ideas with his father and asked for advice about Emma. Speaking from experience, Doctor Robert Waring Darwin told his son to conceal religious doubts which could cause "extreme misery... Things went on pretty well until the husband or wife became out of health, and then some women suffered miserably by doubting about the salvation of their husbands, thus making them likewise to suffer." Charles drew up a list with two columns on a scrap of paper.[69] Under Marry he listed benefits, "Children–if it please God–Constant companion & friend in old age will feel interested in one,–object to be beloved and played with, better than a dog anyhow", while under Not Marry he put "Freedom to go where one liked ... Not forced to visit relatives ... to have the expense and anxiety of children ... fatness & idleness ... if many children forced to earn one's bread ...". He jotted down further thoughts, then concluded "My God, it is intolerable to think of spending ones whole life, like a neuter bee, working, working, & nothing after all. – No, no won't do. – Imagine living all one's day solitarily in smoky dirty London House. – Only picture to yourself a nice soft wife on a sofa with good fire, & books & music perhaps – Compare this vision with the dingy reality of Grt. Marlbro' St. Marry–Marry–Marry Q.E.D."[70]
Then he spent his fortnight being "Very idle at Shrewsbury" which meant starting his "D" notebook on the transmutation sequence and his "M" notebook on the evolutionary basis of moral and social behaviour, filling sixty pages with notes and anecdotes from his father about experiences with patients.
Having come down in favour, he went to visit his cousin Emma on 29 July. He did not get around to proposing, but failed to conceal his ideas on transmutation. Emma noted "he is the most open, transparent man I ever saw, and every word expresses his real thoughts." When she asked about ultimate origins he steered clear of the subject, aware that "it will become necessary to show how the first eye is formed" which he could not yet do.
Malthus and natural law[edit]
After returning to London on 1 August 1838 Darwin read a review of Auguste Comte's Positive Philosophy at the Athenaeum Club. It bolstered his pantheist ideas of natural laws,[71] making him remark "What a magnificent view one can take of the world" with everything synchronised "by certain laws of harmony", a vision "far grander" than the Almighty individually creating "a long succession of vile Molluscous animals – How beneath the dignity of Him"! Only a "cramped imagination" saw God "warring against those very laws he established in all organic nature."[72] His work on Coral Reefs and a paper theorising that Glen Roy had been an arm of the sea soldiered on. He visited the zoo to experiment, observing the reactions of the apes and seeing emotions like "revenge and anger", implying that "Our descent, then, [is the root] of our evil passions." He needed an ally, and hinted to Lyell that his work was "bearing on the question of species", amassing "facts, which begin to group themselves clearly under sub-laws."[73]
Then in late September he began reading "for amusement" the 6th edition of Malthus's An Essay on the Principle of Population which reminded him of Malthus's statistical proof that human populations breed beyond their means and compete to survive, at a time when he was primed to apply these ideas to animal species. Malthus had softened from the bleakness of the earlier editions, now allowing that the population crush could be mitigated by education, celibacy and emigration. Already Radical crowds were demonstrating against the harsh imposition of Malthusian ideas in the Poor Laws, and a slump was resulting in mass emigration. Lyell was convinced that animals were also driven to spread their territory by overpopulation, but Darwin went further in applying the Whig social thinking of struggle for survival with no handouts. His views were secular, but not atheistic. He asked how God's laws had produced "so high a mind" as ours, with purpose shown by descent geared towards the "production of higher animals", suggesting that "we are [a] step towards some higher end".[74][75]
Malthus's essay calculates from the birth rate that human population could double every 25 years, but in practice growth is kept in check by death, disease, wars and famine.[76][77][78][79] Darwin was well prepared to see at once that this related to de Candolle's concept of "nature's war" and also applies to the struggle for existence amongst wildlife,[80][81] so that when there is more population than resources can maintain, favourable variations that allow the organism to better use the limited resources available tend to be preserved, and unfavourable ones destroyed by being unable to get the means for existence, resulting in the formation of new species.[82] On 28 September 1838 he noted this insight, describing it as a kind of wedging, forcing adapted structures into gaps in the economy of nature formed as weaker ones were thrust out. He now had a theory by which to work.[78]
Proposal[edit]
Darwin's thoughts and work continued and he suffered repeated bouts of illness. On 11 November he returned to Maer Hall and proposed to Emma.
Again he discussed his ideas, and she subsequently wrote telling him of her "fear that our opinions on the most important subject should differ widely. My reason tells me that honest & conscientious doubts cannot be a sin, but I feel it would be a painful void between us. I thank you from my heart for your openness with me & I should dread the feeling that you were concealing your opinions from the fear of giving me pain." She continued; "my own dear Charley we now do belong to each other & I cannot help being open with you. Will you do me a favour? yes I am sure you will, it is to read our Saviours farewell discourse to his disciples which begins at the end of the 13th Chap of John. It is so full of love to them & devotion & every beautiful feeling."[83] In the Farewell Discourse from the Gospel of St. John, Jesus instructs his disciples to "love one another", a central part of Christian doctrine which emphasises the need for belief. For Emma the importance of faith had been reinforced by the death of her sister Fanny in 1832, and her need to meet Fanny again in the afterlife. She clearly felt that Darwin would be able to overcome doubt and believe.[84] John 15 also says "If a man abide not in me...they are burned". Darwin's warm reply reassured her, and she replied that "To see you in earnest on the subject will be my greatest comfort & that I am sure you are. I believe I agree with every word you say, & it pleased me that you shd have felt inclined to enter a little more on the subject." However, this tension would remain.[85][86]
Emma's father promised a dowry of £5,000 plus £400 a year, while Doctor Darwin added £10,000 for Charles, to be invested. They decided to move to London until Charles had "wearied the geological public" with his itch to write, then they would "decide, whether the pleasures of retirement & country... are preferable to society."
Marriage[edit]
On 29 December 1838, Darwin took the let of a furnished property at 12 Upper Gower Street. He wrote to Emma that "Gower St is ours, yellow curtains & all", and of his delight at being the "possessor of Macaw Cottage".[99] which he long recalled for its gaudy coloured walls and furniture that "combined all the colours of the macaw in hideous discord",[100] Emma rejoiced at their getting a house she liked, while hoping that they had got rid of "that dead dog out of the garden".[101] Darwin impatiently moved his "museum" in on 31 December, astounding himself, Erasmus and the porters with the weight of his luggage containing geological specimens.[102]
On 24 January 1839 he was honoured by being elected as Fellow of the Royal Society and presented his paper on the Roads of Glen Roy. The next day he took the train home to Shrewsbury, then on the 28th travelled to Maer Hall.
On 29 January 1839, Charles married Emma at Maer, Staffordshire in an Anglican ceremony arranged to also suit the Unitarians, conducted by the vicar, their cousin John Allen Wedgwood. Emma's bedridden mother slept through the service, sparing Emma "the pain of parting". Immediately afterwards Charles and Emma rushed off to the railway station, raising their relative's eyebrows, and ate their sandwiches and toasted their future from a "bottle of water" on the train. Back at Macaw Cottage, Charles noted in his journal "Married at Maer & returned to London 30 years old", and in his "E" notebook recorded uncle John Wedgwood's views on turnips.
See the development of Darwin's theory for the ensuing developments, in the context of his life, work and outside influences at the time.
Note that this article is largely based on Desmond and Moore's book, with commentary summarised in other words and quotations (or extracts from quotations) repeated verbatim.