Thomas H. Huxley: The Separation of Philosophy and Natural Science
The questions of precisely when, why, and how the ‘natural sciences’ became distinguished and then detached from ‘natural philosophy’ remain unresolved, partly on account of difficulties in definition and an absence of clear boundary-markers along the way. For many scholars, this transition happened episodically, perhaps over the eighteenth century, without any specific crisis or revolution that may be said to have precipitated it. John Herschel’s Preliminary Discourse on the Study of Natural Philosophy (1830) is perhaps the last statement of a ‘natural philosophy’ offering a comprehensive framework of engagement of nature, which embraced the question of humanity’s moral relation with the natural world and practices that were appropriate for the meaningful inhabitation of nature.1
Herschel’s work achieved the status of a minor classic, and was read with approval by many, including the young Charles Darwin as a final-year undergraduate at Cambridge University.2 Darwin later recorded his particular appreciation of Herschel’s reflections on the origins of species, which would motivate his own biological reflections: ‘Herschel calls the appearance of new species the mystery of mysteries, & has a grand passage upon the problem!’3 The proper study of nature, for Herschel, was religiously and spiritually fulfilling, and opened the way to reflection on how to enable the ‘collective wisdom’ of humanity to resolve ongoing social problems, by dealing with ‘those obstacles which individual short-sightedness, selfishness, and passion, oppose to all improvement’.4
Yet Herschel increasingly seemed to represent an outlook that was receding into the past. Concerns that studying the natural world could not generate or sustain moral values had gained traction during the later eighteenth century, largely on account of David Hume’s distinction between ‘fact’ and ‘value’.5 Although Hume’s criticism of natural theology or natural religion has attracted much scholarly attention,6 he also raised significant concerns about the idea that the respectful and attentive observation of nature could be morally informative and improving, without the interposition of some bridging theory, which was not itself empirical in its origins.
On the basis of Hume’s analysis, there are two possible ways of understanding the relation of the moral and non-moral realms.7
It was, of course, possible to draw on a theistic framework as a bridging framework between the observation of nature and the ethical inhabitation of nature. As Tamás Demeter points out, the conviction that ‘natural philosophers were studying God’s creation provided the basic ideological framework of early modern science’.8 As we shall see, the nineteenth century saw a growing trend to move away from theistic approaches to nature characteristic of the early modern period to the more ‘naturalist’ approaches associated with Thomas H. Huxley. We shall discuss this point further later in this chapter.
Yet the traditional category of ‘natural philosophy’ was undermined by more than a shifting ideological context; the propriety of continuing to use this term to refer to an essentially empirical discipline became increasingly contested. On at least two occasions during the 1830s, William Whewell suggested (anonymously) replacing ‘natural philosopher’ with the single word ‘scientist’.9 By 1840, Whewell had gone public, and openly advocated the use of this new term. ‘We need very much a name to describe a cultivator of science in general. I should incline to call him a Scientist. Thus we might say, that as an Artist is a Musician, Painter, or Poet, a Scientist is a Mathematician, Physicist, or Naturalist.’10 The term ‘scientist’ resonated with the new cultural mood, and gradually displaced the older vocabulary.
A second development of importance was the emergence of the term ‘science’ in the singular, which appears to be linked with the establishment of the British Association for the Advancement of Science in 1831.11 (The French and German equivalents—the Académie des Sciences, founded in 1666, and the Königlich Preussischen Akademie der Wissenschaften zu Berlin, founded in 1700—used the term ‘science’ in the plural.) At that time, a number of distinct scientific disciplines were in the process of emerging in Great Britain, giving rise to the possibility that these might be seen as unrelated fields of studies, and hence diminish the social and cultural authority of ‘science’ in British culture. ‘The fragmentation of the field of scientific inquiry called forth a vision of its potential unification.’12 In their understandable desire to avoid the isolation of specific individual sciences, the founders of the British Association chose to speak simply of ‘science’ in the singular—and in doing so, may have created an impression that every natural science uses a singular and identical ‘scientific method’, thus failing to take account of the fact that individual sciences develop research methodologies which are specifically adapted to their own objects of study.13
These two related developments gradually changed the cultural landscape of the academic and professional world in the final quarter of the nineteenth century, with older terms—above all, ‘natural philosophy’—increasingly being set to one side as the new vocabulary achieved acceptance. While aspects of the moral agendas of natural philosophy would initially remain embedded within the emerging concept of ‘natural science’,14 its focus now lay elsewhere. In 1879, Thomas H. Huxley set out his own approach to the relation of science and philosophy, which avoids making any reference to the now outdated notion of ‘natural philosophy’, as follows:
Fundamentally, then, philosophy is the answer to the question, What can I know? and it is by applying itself to this problem, that philosophy is properly distinguished as a special department of scientific research. What is commonly called science, whether mathematical, physical, or biological, consists of the answers which mankind have been able to give to the inquiry, What do I know? They furnish us with the results of the mental operations which constitute thinking; while philosophy, in the stricter sense of the term, inquires into the foundation of the first principles which those operations assume or imply.15
‘Natural philosophy’, once seen as a unified field of study, now bifurcated into ‘science’ and ‘philosophy’.16 This led to the gradual erosion of the moral agendas originally associated with the study of nature. This loss of a moral focus on nature was catalysed by the English Industrial Revolution, which was based on new technologies that led to radical degradation of the natural environment and significant social dislocation.17 John Ruskin’s 1884 lectures on the ‘Storm Cloud’ may well represent one of the earliest recognitions of the phenomenon of climate change resulting from industrial activity; yet Ruskin’s concerns are deeper than this, hinting at some of the lost concerns of an older natural philosophy.18 The Industrial Revolution seemed to Ruskin to abandon a respectful engagement with the natural world, leading him to develop his own way of bringing the arts and sciences into contact and constructive dialogue.19 A new vision of nature, engaging both arts and sciences, seemed to be required in the face of a ‘demonstrable threat posed by rapacious industrial capitalism to the lives of people, animals and plants’.20
The scholarly understanding of the phenomenon usually styled ‘the Enlightenment’ has undergone significant change since the 1970s. While often portrayed as an intellectually homogeneous movement, critical historical scholarship has led many to conclude that the ‘Enlightenment’ was essentially a polemical term devised in the nineteenth century to make sense of what had happened in the eighteenth, and locate it within certain privileging narratives of progress.21 It is perhaps best to think of the Enlightenment as a competing series of visions of rationality, rather than a single coherent movement, whose agendas and concerns were often shaped by local concerns, while being informally linked through various networks.22 Yet scholars of the Enlightenment have perhaps not given due account of the importance of Newton’s natural philosophy, which seemed to many of his European admirers to demonstrate the power of human reason to penetrate the mysterious workings of the cosmos.23
Populist accounts of the Enlightenment often portray it as a movement grounded on a culturally and historically invariant reason, which could serve as both the foundation and criterion of reliable human knowledge.24 Yet the precision and persuasiveness of Newton’s natural philosophy led many to adopt the Baconian method of acquiring knowledge inductively through the close observation of nature, which was seen as circumventing the interminable and sterile conflicts among philosophers regarding the meaning and validity of first principles of reason. Rationalist confidence in humanity’s intellectual powers was not primarily affirmed in terms of a priori reasoning, but rather in terms of the a posteriori forms of inductive reasoning developed by Bacon, and so successfully applied by Newton.
While it is true that some leading Enlightenment writers—such as Christian Wolff—attempted to reason from first principles, the outcomes of this process were generally seen to lack the coherence of those offered by Newtonian natural philosophy.25 This was particularly the case with the French Enlightenment, which shows clear lines of influence from Newtonian sources.26 Voltaire spent some thirty-three months in self-imposed exile in England during the 1720s, and appears to have absorbed the new confidence in rational investigation of nature arising from Newton’s legacy.27
Yet an unfortunate outcome of the Enlightenment adoption and partial assimilation of Newton’s natural philosophy was the perceived alignment of Newton’s intellectual achievement with modernist narratives of modernization and progress. Newton was thus read through the prism of the Principia, and was seen as ‘the heroic founding father of secular scientific modernity’,28 rather than as the advocate of a rich and complex natural philosophy. In portraying Newton in this way, Enlightenment writers such as Pierre-Simon Laplace were reading him selectively, assimilating him to their own agendas, and—perhaps most significantly, for our purposes—detaching what would now be seen as Newton’s scientific ideas from their informing context. Newton’s ‘science’ (to use this word anachronistically) was embedded within his wider natural philosophy; his later interpreters either divorced them from this context, or interpreted his ‘natural philosophy’ simply as an older term for ‘natural science’, which could be displaced without intellectual loss or impoverishment.
This historical observation underlies the growing critique of Newtonianism as an intellectual system that was inattentive to the complexity of the natural world, or to the place of humanity as both an observer of and a participant in nature. Such concerns were articulated in the closing years of the eighteenth century in Germany by writers such as Friedrich Wilhelm Joseph von Schelling, who developed a ‘natural philosophy’ (Naturphilosophie) which took full account of humanity’s location within the natural order.29 Nature was to be seen as ‘a self-productive organic whole’, resistant to dissection and rational analysis.30 Goethe espoused a strongly holistic view of nature, insisting upon the unity of nature despite its many individual aspects.31 Although Max Weber’s notion of the ‘disenchantment’ (Entzauberung) of nature represents a twentieth-century interpretation of the changing understanding of nature during the eighteenth century,32 the language of ‘magic’ was used at this time in Germany to refer to a sense that something had been irretrievably lost. The later Romantic poet Joseph von Eichendorff, for example, spoke about nature being able to ‘sing’, if only the ‘Magic Word’ (Zauberwort) could be found to unlock its secrets.33 Yet many would argue that the most perceptive critical assessment of Newtonianism took place within England, mounted initially by poets who believed that the natural world had been impoverished by its reductionist agenda.
William Blake, for example, was strongly critical of Newtonianism, which he considered to be imaginatively and aesthetically emaciated.34 Blake singled out Bacon, Locke, and Newton—the three intellectual archetypes of an experimental natural philosophy—for criticism, apparently on the basis of his mistaken assumption that all three are to be seen as proponents of a mechanical worldview. Blake’s view is probably best known from the familiar line from Jerusalem (1804–20), ‘Bacon and Newton, sheathed in dismal steel’,35 but is set out more fully in these lines lamenting the captivation of the intellectual and cultural mindset of Europe by a mechanical philosophy, in which nature is understood as a machine:
I turn my eyes to the schools and universities of Europe
And there behold the Loom of Locke, whose woof rages dire,
Wash’d by the Water-wheels of Newton: black the cloth
In heavy wreaths folds over every nation: cruel works
Of many Wheels I view, wheel without wheel, with cogs tyrannic
Moving by compulsion each other, not as those in Eden, which,
Wheel within wheel, in freedom revolve in harmony and peace.36
Blake’s decidedly negative evaluation of Newton’s natural philosophy has often been asserted to arise from his direct engagement with Newton’s writings, especially the Principia.37 Yet this seems improbable. Newton’s Principia is notoriously difficult to interpret for those unable to understand its mathematical language. Newton himself declined to offer a popular account of his theories, and thus created a market for popular interpretations of ‘Newtonianism’.38 As a result, discussion of ‘Newtonianism’ was relocated from the academic world, being widely disseminated through public lectures and cheap pamphlets, with the result that ‘coffeehouses formed the matrix of Newtonian persuasion’.39 It is therefore important to note that recent scholarly examination of Blake’s writings has called into question whether Blake had any direct familiarity with Newton’s works, and points rather to Blake being familiar with popular Newtonianism, rather than with Newton’s own works.40 If this is so, Blake’s criticisms are really directed against certain culturally influential readings of Newton, not necessarily Newton himself.
While Blake’s concerns about Newton’s legacy focused on his Principia, other criticisms of this period concerned his Opticks.41 In his rambling 1820 poem ‘Lamia’,42 John Keats was particularly critical of the ‘unweaving’ of the rainbow, protesting against the conquering of a rich and mysterious reality, which reduced it to the realm of the dull and common.
Do not all charms fly
At the mere touch of cold philosophy?
There was an awful rainbow once in heaven:
We know her woof, her texture; she is given
In the dull catalogue of common things.
Philosophy will clip an Angel’s wings,
Conquer all mysteries by rule and line,
Empty the haunted air, and gnomed mine –
Unweave a rainbow.
Although there is no explicit reference to Newton here, some have made a connection with reports of Keats attending a dinner at which Newton was criticized for having ‘destroyed all the Poetry of the rainbow by reducing it to a Prism’.43 Yet once more, questions must be raised about whether Keats had actually read Newton, or whether he was responding to an uninterrogated popular cultural perception about Newton.
Some have interpreted Keats’s protest against a ‘cold philosophy’ to refer to philosophy in the modern sense of that term.44 It is, however, important to appreciate that in 1820 the term was often used as a synonym for ‘natural philosophy’. The fourth edition of the authoritative Encyclopaedia Britannica (1810) offers this descriptive account of the term ‘philosophy’ as it was then used:
The chief object of the philosopher is to ascertain the causes of things; and in this consists the difference between his studies and those of the natural historian, who merely enumerates phenomena and arranges them into separate classes.45
Yet from this definition of philosophy, along with the frequent references to the work of Francis Bacon, it is clear that the term ‘philosophy’ approximates to ‘natural philosophy’. This sense of the term, when applied to Keats’s concerns in ‘Lamia’, make far more sense of his remarks than the notion of philosophy as critical reasoning.46
Perhaps Keats’s real concern, echoed by many within and beyond the Romantic movement, is the increasing emphasis placed upon objectivity in the study of nature.47 Given the importance of this theme for our later reflections, its historical development merits discussion at this point.
Such concepts as ‘objectivity’ and ‘impartiality’ attained the status of epistemological virtues in the late seventeenth and eighteenth centuries, encouraging the view that nature could ‘speak for itself’, without fear of intellectual distortion arising from partisan concerns or cultural precommitments.48 This emphasis on the possibility of an objective account of nature was important within the context of a culture shaped by memories of social tensions and disruptions associated with earlier European Wars of Religion. It is easy to understand the appeal at this time of such an external objective standard of rationality and morality,49 in that it locates epistemic authority beyond human agency. Part of the appeal of a ‘natural philosophy’ was that it represented a set of ideas and values that was grounded in something lying beyond the control and manipulation of humanity. Wordsworth’s lines might be cited in support of this view:
To the solid ground
Of nature trusts the Mind that builds for aye.50
Indeed, such was the appeal of these lines that they were adopted as the motto for the new scientific journal Nature, first published in November 1869.51
Yet it is one thing to be an unbiased interpreter of nature; it is quite another to be a detached observer of the natural world. The ‘subjective turn’ evident in British Romantic writers such as Coleridge and Wordsworth is often understood as resulting from discontentment with ‘the passivity of consciousness in empiricist accounts’ of nature on the one hand, and a growing interest in ‘newer physiological theories of sensation, of subjectivity as constituted by the creative perceptual activity of imagination’ on the other.52 For Wordsworth and Coleridge, the subjectivity of the observer had to be enfolded within any account of the observation of nature. Every ‘act of existential perception’ thus becomes ‘an act to which the perceiver contributes an essential ingredient of his own knowledge’.53 Yet while Romantic writers drew on multiple cultural and intellectual resources in framing and exploring the subjective appreciation of the natural world, the shadow of a ‘scientific other’ appears to hover over these subjective reflections.
While Romantic poets might differ in how they grounded and expressed their subjective concerns, they were clearly concerned at the loss of an affective relational dynamic between the human observer and the natural world. Other voices of the age tried to find ways of reconnecting affectively and imaginatively with the natural world. John Ruskin, for example, was critical of the ‘cold, merely materialist science’ of the middle Victorian period, and sought to recapture the spirit of earlier natural philosophies by explaining ‘what natural forms had meant, intellectually and morally, to previous generations’.54 Yet such attempts at reconnection ultimately seem to have failed to halt or reverse the growing professional and intellectual divergences between the emerging natural sciences and the more traditional arts and humanities.
A conceptually important, though historically extended, transition of importance to our reflections on the changing shape and fortunes of natural philosophy concerns the notions of ‘theistic science’ and ‘naturalistic science’ in the nineteenth century.55 Two major schools of thought found themselves competing for public support in Britain during the nineteenth century: ‘theistic science’, comparable in many ways to earlier forms of natural philosophy, and an emerging ‘naturalist science’.56 Crucially, historians have noted how these two approaches rested on very similar core beliefs (such as the uniformity of nature) and working methods and norms.57
While both theistic and naturalistic approaches to science assumed (and ultimately depended upon) the principle of the uniformity of nature, the former grounded this in an objective divine act of creation, and the latter through an emerging account of the metaphysics of nature. As Huxley pointed out, critical assumptions underlying the sciences—such as the uniformity of nature—are ‘neither self-evident nor are they, strictly speaking, demonstrable’.58 Both theistic and naturalist approaches to science rested on assumptions about the natural order that could not be proved to be correct.
Scientific ‘naturalism’ is not a ‘natural’ category, but is better understood as an ‘actor’s category’, the meaning of which ‘was forged and fought over alongside major developments in the history of science and in British history more generally’.59 This observation helps us understand how Huxley’s ‘descriptive binary’ could be reframed polemically as the ‘prescriptive corollary’ of the ‘warfare’ model of science and religion.60 Yet despite these very different understandings of the metaphysical foundations of natural science, both theistic and natural approaches led to the same theoretical and practical outcomes, using the same norms and methods. Any adjudication concerning which was to be preferred seemed to lie beyond the scope of an inductive method.
With this point in mind, we may turn to what is now widely seen as one of the most significant statements of a ‘naturalistic’ approach to biological science: Charles Darwin’s Origin of Species (1859). Darwin’s assessment of the relative merits of theistic and naturalist approaches to science focused on which appeared to offer the better and more persuasive inductive explanation of certain otherwise puzzling observations of the distribution of biological species.
Darwin did not see himself called upon to prove the existence of biological evolution: that idea had gained credibility since the publication of his grandfather Erasmus Darwin’s Zoonomia (1794–6), and was further reinforced by Jean-Baptiste Lamarck’s Histoire naturelle des animaux sans vertèbres (1815–22). Although some influential voices—such as the geologist Charles Lyell—resisted the idea, Lamarck’s transformist account of evolutionary change was being widely discussed in English scientific circles during the 1850s.61 In 1858, the year before the publication of Darwin’s Origin of Species, Thomas H. Huxley delivered a lecture on the ‘progressive development of animal life in time’, arguing that it was not the evolution of species that was in doubt; the question that remained to be resolved was how this process of progressive development took place.
There is no doubt that the living beings of the past differed from those of the present period; and again, that those of each great epoch have differed from those which preceded, and from those which followed them. That there has been a succession of living forms in time, in fact, is admitted by all; but to the inquiry – What is the law of that succession? different answers are given; one school affirming that the law is known, the other that it is for the present undiscovered.62
This was the main question that Darwin addressed: identifying the natural process that lay behind, and thus explained, the phenomenon of biological evolution.
Although Darwin is often described as a ‘scientist’, his working method actually places him within the Baconian inductive tradition of natural philosophy.63 Darwin was not an experimentalist; rather, he had accumulated a series of observations while sailing round the world on H.M.S. Beagle which seemed difficult to explain using existing understandings of the origins and development of biological life. Darwin’s own account of his discovery of ‘natural selection’64 fits—as he himself suggests—within a Baconian inductive paradigm. Perhaps the best place to start is with the opening paragraph of the Origin of Species:
When on board H.M.S. Beagle, as naturalist, I was much struck with certain facts in the distribution of the inhabitants of South America, and in the geological relations of the present to the past inhabitants of that continent. These facts seemed to me to throw some light on the origin of species—that mystery of mysteries, as it has been called by one of our greatest philosophers.65
During this round-the-world voyage, Darwin made a series of observations about the forms of plant and animal life in various regions, and collected a series of specimens on which he would subsequently reflect on his return to England. The methodology that Darwin describes is that of the accumulation of observations, and attempting to develop a theory which would offer their most satisfactory explanation.
As Darwin reflected on those observations, they seemed to indicate intractable problems and shortcomings with existing understandings of the origins of the biological realm, especially the idea of ‘special creation’ offered by religious apologists such as William Paley in his Natural Theology (1802).66 While Paley’s theory offered explanations of these observations which appealed to Darwin as a young man, he came to see them as increasingly cumbersome and forced.67
A more recently proposed alternative to Paley was Charles Lyell’s notion of ‘natural creation’, which offered a naturalist account of the origin of new species in the light of shifting environmental conditions, which led to the extinction of older species and their replacement by newer forms, better adapted to the altered conditions.68 Yet Lyell was not able to propose a satisfactory mechanism for this process. While a number of explanations could be offered for what Darwin observed during his voyage on the Beagle, the question remained which of these explanations was to be considered the best. Many of Darwin’s observations did not seem to fit easily within the parameters of existing theories. A better explanation, Darwin believed, had to lie to hand.
The natural philosopher William Whewell used a rich visual image to communicate the capacity of a good theory to make sense of, and weave together, observations. ‘The facts are known but they are insulated and unconnected…The pearls are there but they will not hang together until some one provides the string.’69 The ‘pearls’ are the observations; the ‘string’ is a theory that connects and unifies the data. Such a theory, Whewell asserted, allows the ‘colligation of facts’, establishing a new system of relations with each other, unifying what might have otherwise been considered to be disconnected and isolated observations. The ‘pearls’ were the often puzzling observations that Darwin had accumulated; but what was the best string on which to thread them? Two representative sets of observations may be noted.
First, Darwin noted that many creatures possessed ‘rudimentary structures’, which have no obvious or predictable biological function—such as the nipples of male mammals, the rudiments of a pelvis and hind limbs in snakes, and wings on many flightless birds. How might these be explained on the basis of Paley’s theory, which stressed the importance of the individual design of species? Why should God design redundancies? Second, Darwin’s research voyage on the Beagle disclosed an uneven geographical distribution of life forms throughout the world.70 In particular, Darwin was impressed by the peculiarities of remote island populations, such as the finches of the Galápagos islands. While Paley’s doctrine of special creation could account for this, it did so in a manner that seemed forced and unpersuasive.
So what could be inferred from these puzzling observations, to which others could easily be added?71 What was the best explanation of these observations? The best string to connect them? While Darwin knew that his theory of natural selection was not the only possible explanation of the biological data, he believed that it succeeded in making better sense of observations that were otherwise puzzling. The hypothesis of natural selection, he argued, possessed greater explanatory power than its rivals, such as the doctrine of independent acts of special creation, as set out in the writings of William Paley, or Lyell’s proposal of ‘autochthonous generation’.72 ‘Light has been shown on several facts, which on the belief of independent acts of creation are utterly obscure.’73
Yet while Darwin’s theory illuminated natural phenomena, Darwin was quite clear that his theory did not predict, and could not predict. In a letter praising the perspicuity of F. W. Hutton, Darwin singled out this point for special comment.
He is one of the very few who see that the change of species cannot be directly proved, and that the doctrine must sink or swim according as it groups and explains phenomena. It is really curious how few judge it in this way, which is clearly the right way.74
Darwin’s phrase ‘the doctrine must sink or swim according as it groups and explains phenomena’ is significant. The nature of the scientific phenomena was such that prediction was not possible for Darwin. This led some philosophers of science, most notably Karl Popper, to suggest unwisely that Darwinism was not really scientific.75
Yet more recent studies, especially in the philosophy of biology, have raised interesting questions about whether prediction really is essential to the scientific method. This issue emerged as important in the pre-Darwinian nineteenth-century debate between William Whewell and John Stuart Mill over the role of induction as a scientific method.76 Whewell emphasized the importance of predictive novelty as a core element of the scientific method; Mill argued that the difference between prediction of novel observations and theoretical accommodation of existing observations was purely psychological, and had no ultimate epistemological significance. Darwin, however, added a comment to the final edition of the Origin of Species, making it clear that his theory was to be tested by its capacity to accommodate the observational evidence.
It can hardly be supposed that a false theory would explain, in so satisfactory a manner as does the theory of natural selection, the several large classes of facts above specified. It has recently been objected that this is an unsafe method of arguing; but it is a method used in judging the common events of life, and has often been used by the greatest natural philosophers.77
Darwin fits comfortably into the tradition of natural philosopher, as this evolved from Bacon to Newton. Yet his contribution to its future development arguably lies fundamentally in an insight articulated most clearly in the closing statement of The Descent of Man (1871):
We must acknowledge, as it seems to me, that man with all his noble qualities, with sympathy which feels for the most debased, with benevolence which extends not only to other men but to the humblest living creature, with his god-like intellect which has penetrated into the movements and constitution of the solar system – with all these exalted powers – Man still bears in his bodily frame the indelible stamp of his lowly origin.78
The passage clearly strikes a moral tone, locating humanity within the natural order, with imperatives to sympathy and benevolence to other components of that order. Yet it also raises the question of the continuing impact of humanity’s evolutionary history on its present condition. Although Darwin confines his reflection to humanity’s ‘bodily frame’, others would suggest that human instincts and patterns of thought might similarly be shaped by the evolutionary process.79
Yet where Darwin can be argued to have remained within the broad tradition of natural philosophy, his leading interpreter pressed for the separation of philosophy and natural science, and raised concerns about those who suggested that nature could be a moral inspiration for humanity.
Although many leading empirical philosophers of the middle of the nineteenth century saw the natural sciences and philosophy as interconnected,80 Huxley made a bold and decisive distinction between philosophy and science which shaped popular thinking in England during the final quarter of the nineteenth century. Philosophy is the ‘answer to the question, What can I know?’, and science is the response ‘to the inquiry, What do I know?’81 By the later Victorian period, many saw Huxley as embodying the persona of this emerging scientific culture, creating a normative public understanding of science through his public lectures and publications.82 Huxley’s introductory ‘science primers’ secured him a wide popular readership, and helped shape the new cultural confidence in the natural sciences. ‘Natural philosophy’ now came to be seen as an outdated way of referring to the natural sciences, which had been left behind as a result of the rapid scientific advances of the nineteenth century.
So what do we know? Huxley’s answer, though easily stated, is perhaps less easily applied. ‘In strictness all accurate knowledge is Science; and all exact reasoning is scientific reasoning.’83 Yet this statement, found in what was intended to be a popular science textbook, is probably to be seen as a pedagogical overstatement, formulated with the need for simplicity of argument in mind. Elsewhere, Huxley is much more guarded and cautious, concerned to emphasize what can be known through science, while applying the maxim ignoramus et ignorabimus (‘we do not know and we will not know’) to the shadowy region that lay beyond the application of the scientific method.84 Yet Huxley’s influential formulation of the relation of science and philosophy can be seen to fit into an overall cultural narrative relating ‘how science, through the provision of cognitive norms, came to serve as a model for all forms of purposive behaviour’.85
While some argued that Huxley’s celebrated agnosticism was ultimately devised to evade awkward questions about the grounds and justification of his own ideas,86 Huxley himself saw it as the inevitable and proper outcome of a scientific approach to knowledge, which was willing to accept both the provisionality and the fallibility of its conclusions. He made this point as follows in a series of lectures to ‘working men’, delivered at the Museum of Practical Geology in 1862:
Men of science do not pledge themselves to creeds; they are bound by articles of no sort; there is not a single belief that it is not a bounden duty with them to hold with a light hand and to part with cheerfully, the moment it is really proved to be contrary to any fact, great or small.87
Huxley was not, however, entirely consistent on this point, elsewhere pointing out the need to accept certain unprovable assumptions entailed by the scientific method:
The one act of faith in the convert to science, is the confession of the universality of order and of the absolute validity in all times and under all circumstances, of the law of causation. This confession is an act of faith, because, by the nature of the case, the truth of such propositions is not susceptible of proof. But such faith is not blind, but reasonable.88
Although acknowledging the importance of Hume as a philosopher, Huxley’s emphasis on the advancement of human civilization through scientific progress led him to detach scientific research, reasoning, and application from its earlier philosophical contextualizations. Whereas earlier natural philosophers saw nature as an important stimulus to ethical reflection, Huxley—following Hume—declined to ground moral reflection in the structures or processes of the natural world.
For Huxley, scientists were ‘graduates in the University of Nature’,89 who had learned how to study the order and laws of the natural world. In a lecture of 1868, Huxley declared that:
Nature is still continuing her patient education of us in that great university, the universe, of which we are all members. Those who take honours in Nature’s university, who learn the laws which govern men and things and obey them, are the really great and successful men in this world.90
Yet while Huxley’s early essays on the importance of science education reproduce some themes traditionally associated with natural philosophy,91 particularly achieving harmony with the natural order, his enthusiasm for this older vision appears to have faded over time.
While some later Victorian thinkers tended to see evolution in terms of a progressive ethic of self-improvement,92 Huxley rejected this interpretation of the evolutionary process. His 1893 Oxford lecture on ‘Evolution and Ethics’ is perhaps one of the most important expressions of the gap that Huxley had opened up between the study of the natural order and the human quest for civilization and values.93 Where earlier transformist accounts of evolution were easily assimilated to an ethic of self-improvement, Darwin’s approach—especially in its appeal to Malthus’s Essay on Population—presented evolution in terms of competition between species.94
In some prefatory comments to this lecture, Huxley identified his intention to resolve ‘the apparent paradox that ethical nature, while born of cosmic nature, is necessarily at enmity with its parent’.95 For Huxley, human beings are animals who have triumphed in the ‘struggle for existence’ on account of their capacity for violence and destruction. Yet with the emergence of civilization, the animal characteristics which allowed human beings to triumph in this struggle are no longer seen to be ‘reconcilable with sound ethical principles’.96
Ethics, for Huxley, is now a principled resistance to precisely those animal qualities that had earlier secured human domination of the living world, and the Darwinian processes that underlie them. We must therefore learn to conquer and subdue the natural animal instincts that linger within us. Our hereditary history continues to shape our present—and it must be resisted, even though it cannot be eradicated. ‘The practice of that which is ethically best – what we call goodness or virtue – involves a course of conduct which, in all respects, is opposed to that which leads to success in the cosmic struggle for existence.’97 While the natural process of evolution may explain the origins of human ethics, it cannot now function as the basis of ethics. Evolution ‘may teach us how the good and the evil tendencies of humanity may have come about; but, in itself, it is incompetent to furnish any better reason why what we call good is preferable to what we call evil than we had before’.98
Huxley thus offers a Darwinian basis for the rejection of traditional natural philosophies (though he does not use the term ‘natural philosophy’ in this lecture).99 This is expressed most forcefully in his rejection of the ‘stoical summary of the whole duty of man, “Live according to nature”’, which seems to imply that the cosmic process is ‘an exemplar for human conduct’.100 At the risk of overstating this important point, Huxley comes close to suggesting that the close observation of natural world shows us how not to behave. This contrasts sharply with one of the core themes of early modern natural philosophy—that of learning from nature, and not simply learning about nature. This idea—perhaps most dramatically expressed by Alexander Pope in his Essay on Man (1733–4): ‘Great Nature spoke; observant Men obey’d’101—was now firmly relegated to an outmoded and unusable past.
This chapter has documented the gradual parting of the ways between the natural sciences and philosophy, and the dissolution of the notion of ‘natural philosophy’ as a viable field of study and research. Yet this need not be the end of the story of natural philosophy. In the second part of this work, we shall consider how this category might be reimagined and repurposed, given the increasingly urgent need of supplementing a scientific approach to the natural world with one that is attentive to wider questions, raised—yet not answered—by the natural sciences.