Martin Meisel, “On the Age of the Universe”


The Charles Darwin-inspired debate over the Age of the Earth that pitted contemporary Physics against the theory and practice of contemporary Geology was intimately tied to recent unsettling projections on the thermodynamic fate of the universe. The leading voices in the debate were William Thomson, later Lord Kelvin, and Thomas Henry Huxley, Darwin’s most able champion. The argument—resolved only in the next century—has exemplary value as an intractable dissonance between two vigorous and well established, but not entirely secure scientific disciplines. And its content laid some of the groundwork for the pessimism that qualified the cult of progress and the whiggish habits of cultural and material complacency towards the end of the century.

The Fate of the Universe

In 1852, William Thomson, later Lord Kelvin, delivered a short, startling paper to the Royal Society of Edinburgh called, “On a Universal Tendency in Nature to the Dissipation of Mechanical Energy.”  Its object, he said, was “to call attention to the remarkable consequences which follow from [Nicolas Léonard Sadi] Carnot’s proposition, that there is an absolute waste of mechanical energy available to man when heat is allowed to pass from one body to another at a lower temperature by any means not fulfilling his criterion of a ‘perfect thermo-dynamic engine’“ (510), that is, in all actual circumstances.  From the newly refounded dynamic theory of heat (heat as motion) on the one hand, which said you cannot recover spent mechanical energy from the heat of something no warmer than its surroundings, and from the conservation of energy principle on the other, which allowed of no additions to the existing store, Thomson thought to extrapolate to the largest of systems, the “thermo-dynamic engine” of the whole physical world.  These were his general conclusions:

1.  There is at present in the material world a universal tendency to the dissipation of mechanical energy.

2.  Any restoration of mechanical energy, without more than an equivalent of dissipation, is impossible in inanimate material processes, and is probably never effected by means of organized matter, either endowed with vegetable life or subjected to the will of an animated creature.

3.  Within a finite period of time past, the earth must have been, and within a finite period of time to come the earth must again be, unfit for the habitation of man as at present constituted, unless operations have been, or are to be performed, which are impossible under the laws to which the known operations going on at present in the material world are subject.


Within months, the Glasgow scientist and engineer, W. J. Macquorn Rankine, took up Thomson’s conclusions, attested their soundness, and offered an imaginative way out.[1]  In a direct response to Thomson’s paper, he reports it as showing that there is “a tendency towards a state in which all physical energy will be in the state of heat, and that heat so diffused that all matter will be at the same temperature; so that there will be an end of all physical phenomena” (201).  But Rankine speculates on another possible outcome: that at some “indefinitely distant period” the diffused energy may be reconcentrated, as it encounters the limits of the transparent interstellar medium—in effect the limits of the universe—and is reflected and reconcentrated into “foci” capable, for example, of rekindling an extinct star. Thus,

although, from what we can see of the known world, its condition seems to tend continually towards the equable diffusion, in the form of radiant heat, of all physical energy, the extinction of the stars, and the cessation of all phenomena; yet the world, as now created, may possibly be provided within itself with the means of reconcentrating its physical energies, and renewing its activity and life. (202)

Rankine goes further, in a final speculation that these processes may go on simultaneously.  He thus varies from a cyclically oscillating model (anticipating some twentieth-century hypotheses on the fate of everything), to a dynamic equilibrium model (on a principle favored by other nineteenth-century thinkers, like Herbert Spencer, concerned to accommodate countervailing tendencies of evolution and dissipation).  A universe that is both infinitely expansive and infinitely self-renewing, as in the century-old grand vision of Immanuel Kant, he can no longer reconcile with thermodynamic principle; but Kant’s models nevertheless would be invoked in one of the greatest scientific arguments of the age, Thomson’s thermodynamic challenge to the physical premises of Charles Darwin’s theory of evolution.[2]

Rankine did not persist in his speculative flight from the logic of an inexorable descent into a diffused universal sameness; and in his subsequent “Outlines of the Science of Energetics,” he quietly accepts the inevitable.[3]  Thomson’s conclusions had their own imaginative appeal, as well as convincing mathematical support, and in a little more than a year after his original paper saw print, Hermann von Helmholtz brought the news to a wider audience.  Lecturing, not as a scientist speaking to scientists, but on a civic occasion, Helmholtz describes a universe whose total store of energy is divided into two parts: the heat that is no longer available, and all the rest; where:

the first portion of the store of force, the unchangeable heat, is augmented by every natural process, while the second portion, mechanical, electrical, and chemical force, must be diminished; so that if the universe be delivered over to the undisturbed action of its physical processes, all force will finally pass into the form of heat, and all heat come into a state of equilibrium.  Then all possibility of a further change would be at an end, and the complete cessation of all natural processes must set in.  The life of men, animals, and plants could not of course continue if the sun had lost his high temperature, and with it his light–if all the components of the earth’s surface had closed those combinations which their affinities demand.  In short, the universe from that time forward would be condemned to a state of eternal rest. (74)[4]

Helmholtz softens the blow—parenthetically—by crediting Thomson with seeing in Carnot’s law “consequences which threatened the universe, though certainly after an infinite period of time, with eternal death.”  In taking up the more local and imaginable question of the fate of the earth, he considers the agents and evidences of mortality: evidence for a resisting interplanetary medium in the decay of cometary orbits; the effect of the friction of the tides (“after millions of years” stilling the earth’s rotation); and above all the gradual depletion of the energy of the sun, to which Thomson would soon bring his colder fire.  In the end, Helmholtz offers the odd consolation that the past history of the earth shows “what an insignificant moment the duration of the existence of our race upon it constitutes”; and moreover, there was every likelihood that geological disaster would bring on “the last day of the human race” (89) before the slower-acting thermodynamic inevitabilities could do their worst.

Helmholtz thus evades the peculiarly distressing notion of the death of the universe through senile exhaustion and paralysis by offering, as comfort, a more familiar, violent chaos of destructive convulsion, full of elemental, geologic energy.  He offers one other consolation, more elevating and more flattering, and certainly anti-entropic: that of the light spun out of darkness, irradiating “the distant nights of the beginning and the end of the history of the universe,” by science itself (90).

It was finally Rudolf Clausius who seems to have brought the clearest historical understanding to the relation of the two laws of thermodynamics.  When it comes to the universe, he says, one often hears that everything is a circuit; that when changes occur in one place, at one time, and in a certain direction, in another place and at another time changes will occur in the opposite direction, so that “in the long run the state of the world remains unchanged.  Consequently, it is said, the world may go on in the same way forever” (417).  The Conservation law, he suggests, “may probably have been regarded as an important confirmation of this view”; and indeed, “it expresses the unchangeableness of the universe in a certain very important respect.”  But as to the whole condition of the universe, it leaves something out: the implications of “the second fundamental theorem,” which distinctly preclude an endless recycling.  These are that “the condition of the universe must gradually change more and more in a certain particular direction”; that the work the forces of nature are capable of performing, “contained in the existing motions of the bodies which make up the system of the universe, will be gradually converted more and more into heat”; and heat, “inasmuch as it always tends to pass from hotter to colder bodies, and so to equalize existing differences of temperature, will gradually acquire a more and more uniform distribution” (418). Further (and here Clausius’s reasoning carries him beyond Thomson or Helmholtz), “in relation to their molecular arrangement, material bodies will get nearer to a certain condition in which, regard being had to the existing temperature, the total disgregation is the greatest possible.”  Restating his formula, “The entropy of the universe tends towards a maximum,” Clausius concludes with a Beckettian glimpse of the endgame:

The more the universe approaches this limiting condition in which the entropy is a maximum, the more do the occasions of further changes diminish; and supposing this condition to be at last completely attained, no further change could evermore take place, and the universe would be in a state of unchanging death.[5] (419)

Ancestral Voices

The imagination of a cosmic condition where progressive dissipation has annulled all, or almost all, kinetic interaction did not have to wait for the invention of thermodynamics.  Epicurus evokes it to exclude the possibility of a universe made up of finite matter in infinite space (“the void”):  “For if the void were infinite and bodies finite, the bodies would not have stayed anywhere but would have been dispersed in their course through the infinite void, not having any supports or counter-checks to send them back on their upward rebound” (571-2).[6]  Through such dissipation, it is clear, all structure and differentiation would be lost, along with kinetic interaction.  Epicurus’s point is that such a condition is plainly at odds with the observable reality, but indubitably would have arrived (given unlimited duration and uniform laws) in the kind of universe he is disproving.

Portrait of Buffon

François-Hubert Drouais, Portrait de Georges-Louis Leclerc, comte de Buffon

In eighteenth-century France, the great naturalist Comte de Buffon gave a history of the formation of the earth in his Époques de la nature (1779) that tied its future as well as its past to its internal heat and inevitable refrigeration—however deferred and qualified by the climate-changing actions of man.  At about the same time, another savant, on good terms with Buffon and familiar with his earlier work, composed a philosophic “bagatelle,” as he called it, which specifically contemplates the death of the sun.  Known as “The Ephemera,” and written to the much younger Madame Brillon after a summer’s-day visit to the Moulin Joli (an island in the Seine), Benjamin Franklin’s gallant epistolary fable reports the sage musings of “a kind of little Fly, called an Ephemere, all whose successive Generations we were told were bred and expired within the Day”:

It was, says he, the Opinion of learned Philosophers of our Race, who lived and flourished long before my time, that this vast World, the Moulin Joli, could not itself subsist more than 18 Hours; and I think there was some Foundation for that Opinion, since by the apparent Motion of the great Luminary that gives Life to all Nature, and which in my time has evidently declin’d considerably towards the Ocean at the End of our Earth, it must then finish its Course, be extinguish’d in the Waters that surround us, and leave the World in Cold and Darkness, necessarily producing universal Death and Destruction.

A prodigy of longevity (having lived seven hours and with perhaps seven or eight minutes still in store), the ephemere reflects on the vanity of effort and achievement, and even lasting fame; for “what will become of all History, in the 18th Hour, when the World itself, even the whole Moulin Joli, shall come to its End, and be buried in universal Ruin?”[7] (433-35).

It is not easy to pin down Franklin’s witty fable, which is part of its delight; but along with the compliment to an intelligent amitié, and the Solomonic descant on the vanity of human achievements and large ambitions, with the hinted wisdom of making the most of the moment, the fable pleasantly ridicules the scientific opinion that the ephemere so plausibly supports.  Reports of the immanent death of the world are, it seems, greatly exaggerated.  Mortality and dissolution, in “the Course of Nature,” strike down the single life and even the polity (the sage expects that the present race of ephemeres will, in minutes, “become corrupt like those of other and older Bushes, and consequently as wretched”); but the cycling permanence of Nature and the cosmos is another matter.  Franklin here, as a man of the eighteenth century, appears, cosmologically at least, more mainstream than revolutionary.

Buffon’s own view of the matter, reaching print in the Époques the following year, had recently changed.  A few years earlier he had expounded a view of the cosmos that celebrated its inertial stability, and included the theory of a wheeling solar system whose motion generated heat and light, guaranteeing that the sun, “This fertile source of light and life will never be exhausted, will never run dry”[8] (Roger 386-7).  Buffon retained a belief in a sustaining balance of forces in the universe at large; but by the time of the Époques de la nature, he had come to believe that the earth nevertheless would die of cold, since “The heat conveyed to the earth by the sun is very small when compared to the heat proper to the globe; and this heat transmitted by the sun would not alone be sufficient to support animated nature” (210).  Meanwhile the earth, once molten, was imperceptibly cooling, and having reached a habitable temperature some 72,000 years earlier, “an equal portion of time must elapse before it is so cold as to be unfit for the nourishment of animals and vegetables” (237). Both the issue of the sun’s energy as a renewable or depleting resource, and the earth’s internal heat as an index to its life span, would return to stage center in less than a hundred years, but speaking the language of thermodynamics.

In the interval, however, in a radically different climate of thought and feeling, Shelley’s avid scientific imagination absorbed The Epochs of Nature.  Awed by the glaciers of the Alps, their destructive power and apparently inexorable advance, he recalls Buffon’s “sublime but gloomy theory—that this globe which we inhabit will, at some future period, be changed into a mass of frost by the encroachments of the polar ice, and of that produced on the most elevated points of the earth” (qtd. in Hughes, 228).  And he writes in “The Triumph of Life” of “the great Winter” that will “lay the form and name / Of this green earth . . . for ever low (126-7).”[9]  In a similar spirit, Byron’s startling poem of 1816, “Darkness,” envisages the consequences of the extinction of the sun, in “a dream which was not all a dream” (1).  The death of the sun appears sudden and catastrophic, however, rather than as the result of a slow, inevitable decay.  The rapid disintegration that follows, on “the icy Earth . . . blind and blackening” (4-5), is above all social and structural collapse, with famine and conflagration leading men and cities (and the presumably less rational inhabitants of the earth) to hasten their own extinction.  The poem permutes traditionally apocalyptic imagery; but the end state is one that the imaginative writers of the fin de siècle and after—H. G. Wells, Camille Flammarion, Samuel Beckett—could hardly improve upon as a vision of terminal entropy:

. . . The World was void,

The populous and the powerful was a lump,

Seasonless, herbless, treeless, manless, lifeless—

A lump of death—a chaos of hard clay.

The rivers, lakes, and ocean all stood still,

And nothing stirred within their silent depths;

Ships sailorless lay rotting on the sea,

And their masts fell down piecemeal: as they dropped

They slept on the abyss without a surge—

The waves were dead; the tides were in their grave,

The Moon, their mistress, had expired before;

The winds were withered in the stagnant air,

And the clouds perished; Darkness had no need

Of aid from them—She was the Universe.[10]


Byron’s poem extends a dark strain in post-Revolutionary feeling, as much historical as eschatological, a strain that appears in the numerous representations, from Constantin-François Volney’s Les Ruines forward, of solitary figures brooding over a desolate waste, the trace of empires brought low by catastrophe or the decadence that leads to catastrophe. Mary Shelley’s Last Man(1826), like “Darkness,” goes further, in projecting the death of the world, or at least of all mankind, through a universal plague; but the dominant trope in her novel is still that of unanticipated catastrophe.  The potent “School of Catastrophe” in the art, literature, and popular theater of the earlier nineteenth century most commonly took its cue from Biblical models, even where the subject was secular (e.g. Pompeii).  Nevertheless, in the work of some artists, such as the painter John Martin, scientific views of the history of the earth also left their mark, notably the arguments of Georges Cuvier, and those geological reasonings upon the evidence of formidable “plutonic” and “neptunian” activity in the past subsumed in the 1830s under the label of “Catastrophism.”

James Thomson, Portrait of Georges Cuvier

Undoubtedly the appetite for catastrophic fantasy was greatly spurred by Cuvier’s grand overview and argument, the Discours préliminaire to his work on large fossils (1812), where he reads the past from its physical remains as a series of great terrestrial catastrophes, the latest some six thousand years ago.  Widely translated, it came into English in 1813 as an Essay on the Theory of the Earth.[11]  Byron echoes it in the cosmic retrospect of lost and alien worlds that Lucifer offers the eponymous protagonist in Cain (1821).  Confronted with the shades of Earth’s former glories and its vanished mighty inhabitants (Lucifer hints at the succession of species), Cain asks how such a thing could come about.  Lucifer replies:

By a most crushing and inexorable

Destruction and disorder of the elements,

Which struck a world to chaos, and a chaos

Subsiding has struck out a world: such things,

Though rare in time, are frequent in eternity.[12]


The provocatively unaddressed question here is how do these two orders—time and eternity—relate?  What, speaking materially and concretely, are the dimensions, the confines, of time? And how, practically speaking, does one take its measure?

A Question of Time

The science of geology acquired its name and its modern foundations in the century between 1750 and 1850; and given that the earth, with a physical history of its own, was necessarily the platform on which the drama of organic life—now in medias res—played out, geology found itself both surrogate target and battleground when William Thomson brought his reach and authority in the physical sciences to bear on Darwin’s evolutionary biology.  By then, geological “Catastrophism,” the dominant school in the Romantic period, had been largely displaced by “Uniformitarianism,” both terms the coinage of William Whewell in a critical 1832 review of  Charles Lyell’s Principles of Geology, the treatise that—by virtue of its powers of synthesis, clarifying impetus in a heterogeneous field, and confidence in its subject’s full scientific integrity—would establish itself as the Uniformitarian bible (126).[13]  Darwin was then able to rest his great account of the evolutionary process in organic life on the foundations of modern geology as embodied in Lyell—that is, upon the geology thanks to which, as Thomas Henry Huxley put it in retrospect, “the abyss of time began to loom as large as the abyss of space” (“Progress of Science” 98). Cuvier had earlier exclaimed, “Genius and science have burst the limits of space and .  .  . have unveiled the mechanism of the universe.  Would it not also be glorious for man to burst the limits of time .  .  . and why should not natural history also have one day its Newton?” (3-4). But Cuvier’s time was constrained, at least for the most recent phase of the earth’s history, by a roughly Biblical chronology, allowing no time for gradual transformation, either of species—which he believed invariable—or of continents.  For the slow processes of natural selection as the key to speciation and change, Darwin needed an “abyss of time,” virtually unlimited, one that the patient fossil writing in the rocks and a gradualist explanation of their succession could supply.

“Gradualist” could as easily have been the summary tag as “Uniformitarian” for the school of Lyell and his pioneering predecessors, James Hutton and John Playfair, except that “Uniformitarian” asserted a methodological and indeed philosophical premise. This was that the processes at work today are the only fit instrument for interpreting the geological past; and that a theory of the earth (in Hutton’s words) “can have no retrospect to that which had preceded the present order of the world; for this order alone is what we have to reason upon” (254). As T. H. Huxley was obliged to admit, Hutton, who laid the disciplinary groundwork at the end of the eighteenth century, was no evolutionist, but saw in the stable, compensatory system of the heavens, confirmed by French celestial mechanics, a model for the system of the earth, a “succession of worlds” whose processes revealed “no vestige of a beginning,—no  prospect of an end” (255).[14] Nevertheless, Hutton’s slow processes of crustal erosion and deposition in the depths of the sea, consolidation of the sediments, their elevation, subjection to plutonic forces and intrusions, and then new erosion and sedimentation, in endless cycle, offered a lodgment for theories of evolution, stratigraphic or bioform, without temporal constraint.

In 1862, William Thomson, having already looked to the end of things, turned his attention to beginnings.  Three years after The Origin of Species, he published an essay in Macmillan’s Magazine whose intent clearly included the desire to challenge Darwin and his supporters on their premises before a large public.  He did so by squarely confronting the immense tracts of time that evolution through natural selection required, with the temporal limits derived from physical law, notably thermodynamics. Selecting from among the several problematic assumptions in the evolutionists’ generous construction of geological time, he focuses here “On the Age of the Sun’s Heat.” By eliminating chemical combustion or meteoric renewal (a theory he had earlier embraced) as adequate energy sources, Thomson bases his estimates on the radiant energy of an incandescent mass whose heat derives from initial coalition and gravitational contraction.  Calculating from the probable rate of cooling and the constraining limits on the sun’s initial and specific heats, Thomson concludes that it is “on the whole most probable that the sun has not illuminated the earth for 100,000,000 years” (393). With an eye to this relative brevity, he asks, “What then are we to think of such geological estimates as 300,000,000 years for the ‘denudation of the Weald,’”  and, getting personal, “Whether it is more probable that the physical conditions of the sun’s matter differ 1,000 times more than dynamics compel us to suppose they differ from those of matter in our laboratories; or that a stormy sea, with possibly channel tides of extreme violence, should encroach on a chalk cliff 1,000 times more rapidly than Mr. Darwin’s estimate of one inch per century?” (391-92).[15]

In the introduction to his mostly expository article, after stressing the unassailable authority of “the second great law of Thermodynamics,” and that “principle of irreversible action in nature” whose result “would inevitably be a state of universal rest and death.” Thomson hastens to cushion the harshness of the sentence. He informs his readers that, in a universe with no conceivable limits, “science points rather to an endless progress, through an endless space, of action involving the transformation of potential energy into palpable motion and thence into heat, than to a single finite mechanism, running down like a clock, and stopping for ever” (388).  Moreover, with the need for “an overruling creative power” to account for life in the first place, “no conclusions of dynamical science regarding the future condition of the earth, can be held to give dispiriting views as to the destiny of the race of intelligent beings by which it is at present inhabited” (389).  But he concludes with the certainty that these same inhabitants of the earth “cannot continue to enjoy the light and heat essential to their life, for many million years longer, unless sources now unknown to us are prepared in the great storehouse of creation” (393).[16]

A month later, Thomson invoked a second physical ground for faulting the Uniformitarian time scale in a paper read to the Royal Society of Edinburgh, “On the Secular Cooling of the Earth.”  Here, reasoning from irreversible dissipation, the increase of temperature with depth in the earth, and the implication of continual heat loss through conduction outwards, Thomson presents the probability of a (hotter) catastrophic past, and, in passing, he openly scoffs at Lyell for proposing an internal economy for the earth of perpetually cycling electro-chemical renewal as being no less fanciful and at odds with physical law than a perpetual-motion clock.  He arrives at wide outer limits for the consolidation of the earth—between twenty and four hundred million years ago (300)—not to be confused with life-form habitability.  And he sets the stage for his all-out challenge, delivered in 1868 in the very citadel of error, as an address to the Geological Society of Glasgow “On Geological Time.”[17]

Calling for “A GREAT [sic] reform in geological speculation”(10), Thomson adds to his arguments on the age of the sun’s heat and the cooling of the earth those from frictional resistance, notably the retarding effects of the tides on rotation.  Beginning with a “celebrated” and extensive passage from Playfair’s redaction of Hutton declaring, among other things, that “The Author of nature has not given laws to the universe, which, like the institutions of men, carry in themselves the elements of their own destruction,” Thomson observes, “Nothing could possibly be further from the truth”(12). British popular geology, he finds, “at the present time is in direct opposition to the principles of natural philosophy” (44).  Far from there being, as Playfair put it, no permitted sign in His works “by which we may estimate either their future or their past duration” (12), the earth, Thomson asserts, “is filled with evidences that it has not been going on forever in the present state, and that there is a progress in events towards a state infinitely different from the present” (44).  Looking forward, to the long-term effects of tidal friction on the earth’s rotation, he projects a cessation of the motion of the earth relative to the moon; looking back, to a sun expending its heat and an earth cooling from the liquid state, he concludes that “the existing state of things on the earth, life on earth, all geological history showing continuity of life, must be limited within some such period of past time as one hundred million years” (64).

The gauntlet having been flung down, the redoubtable Thomas Henry Huxley rose to the defense of fair Geology.  In a parallel venue, one year later, Huxley delivered his Presidential Address to the Geological Society of London on the subject of “Geological Reform.”  Using courtroom metaphors for his refutation of Thomson’s charges against the profession, he dismisses the conclusiveness of Thomson’s temporal estimates even if correct.  He argues the vagueness of their upper and lower limits, and (correctly as it happens) the likelihood of crucial unknowns; but also that, with no absolute time scale written in the geological record, “one or two hundred million years might serve the purpose, even of a thorough-going Huttonian uniformitarian, very well” (278).  Rebuttal of the factual argument is not where Huxley begins, however.  He repudiates the notion that geological thought is monolithic, and instead lays out “three, more or less contradictory, systems,” all with something to be said for them (252).  To Catastrophism and Uniformitarianism in their hardened opposition, he adds Evolutionism, which, like Evolution itself, “embraces all that is sound in both Catastrophism and Uniformitarianism, while it rejects the arbitrary assumptions of the one and the, as arbitrary, limitations of the other” (267).  Rather too neatly, he characterizes the one (Catastrophism) as insisting on “the existence of a practically unlimited bank of force,” while the other (Uniformitarianism) upon “a practically unlimited bank of time”(266-7), and finds no necessary theoretical antagonism between them.  But his defense is much more attentive to Uniformitarianism and its secular continuities, and his own evolutionistic disposition to relate inorganic and organic processes leads him to foreground Hutton’s venture beyond considering the earth “merely as a machine” when accounting for the earth’s durability.  “May it not be also considered as an organized body?” Hutton had asked, “such as has a constitution in which the necessary decay of the machine is naturally repaired, in the exertion of those productive powers by which it had been formed” (256). On the other hand, under the cover of an appeal for a speculative “geological aetiology,” Huxley invokes Kant’s cosmogony as a kind of progressive Catastrophism:

In vivid language he depicts the great world-maelstrom, widening the margins of its prodigious eddy in the slow progress of millions of ages, gradually reclaiming more and more of the molecular waste, and converting chaos into cosmos.  But what is gained at the margin is lost in the centre; the attractions of the central systems bring their constituents together, which then, by the heat evolved, are converted once more into molecular chaos.  Thus the worlds that are, lie between the ruins of the worlds that have been and the chaotic materials of the worlds that shall be; and, in spite of all waste and destruction, Cosmos is extending its borders at the expense of Chaos. (264)

Kant’s expanding universe, like Hutton’s organic analogy, appeals to Huxley in opening the way for evolutionary schemata that transcend any particular content or discipline:

Nor is the value of the doctrine of Evolution to the philosophic thinker diminished by the fact that it applies the same method to the living and the not-living world; and embraces, in one stupendous analogy, the growth of a solar system from molecular chaos, the shaping of the earth from the nebulous cubhood of its youth, through innumerable changes and immeasurable ages, to its present form; and the development of a living being from the shapeless mass of protoplasm we call a germ. (267-68)

Moreover, not only is evolutionary succession a way of ordering a complex dynamic reality, it also gives positive value to the direction of time: time here is not a measure of depletion and dissolution, of the clock of the cosmos running down, but of cosmic advance “at the expense of Chaos.”

Thomson returned to the charge six weeks later, once more addressing the Geological Society of Glasgow (“Of Geological Dynamics”). Huxley had laid on him the burden of proving geology’s derelictions, and he responds by quoting from textbooks and treatises, culminating in the latest edition (1868) of Lyell’s Principles of Geology.  He quotes a long passage wherein Lyell invokes the convertibility of forces, and implicitly the conservation law, to counter “this theory of the constant diminution from age to age” of the sun’s power (109).  For Thomson, it is the clinching example of geology’s “same tendency to overlook essential principles of thermodynamics,” that is, the Second Law (108).  Consequently, it is no sounder than “Kant’s hypothesis of the restoration of a new chaos, like the old one, with potential energy for a repetition of cosmogony” (110).  The “new chaos” that the Second Law projected was precisely not chaos recharged, but rather, chaos gone flat.

Thomson claims that his own geological training, before “the ultra-uniformitarianism of the last twenty years,” embodied the fundamental theory that Huxley now calls Evolutionism (77); and that “the Catastrophism of Leibnitz, Newton, Sedgwick . . . and many other true geologists” was nothing less than that same “‘evolutionism’” (111).  But the crux of his forensic replication on the basic issues raised in his original charge, “On Geologic Time,” lies in his rejection of Huxley’s breezy reassurance that, “If the geological clock is wrong, all the naturalist will have to do is to modify his notions of the rapidity of change accordingly.”  Thomson refuses to accept the view that such a correction would be a trivial matter for what he calls “biological speculation.” “The limitation of geological periods, imposed by physical science, cannot, of course, disprove the hypothesis of transmutation of species; but it does seem sufficient to disprove the doctrine that transmutation has taken place through [the slow-acting] ‘descent with modification by natural selection’” (89-90).

The argument did not end there, of course, and it has a special place in the history of science as an episode in which two powerful disciplinary constructs at odds with each other—not simply unreconciled, like quantum theory and relativity, but seeming to invalidate each other’s premises and conclusions—continue in force in their respective disciplines because they are so genuinely productive and richly self-validating.  Thomson’s thermodynamic case against the geologic time required by the Darwinians ought to have been a true sticking point, resting as it does on physical “law” and the authority it has carried since Newton combined with an audit of energy supplies and expenditures that is, if anything, generous in its estimates.  Even on the Huttonian principle of reasoning strictly from the world we know, Thomson has the better arguments. But of course his case collapses with the outing of what he had no way of knowing: radioactive decay as a measure of the age of the earth as well as contributing to its heat, and fusion as fueling the sun’s.[18]

In 1897, ironically less than a year after Henri Becquerel’s discovery of radioactivity in uranium, Thomson, now Baron Kelvin, spoke once more on “The Age of the Earth as an Abode Fitted for Life.”  In this Presidential Address to the Victorian Institute in London, he reviews the whole long debate and declares that his conclusions, now as then—now refined through experimental investigation—suffice “to sweep away the whole system of geological and biological speculation demanding an ‘inconceivably’ great vista of past time, or even a few thousand million years” (213). Ten years earlier he had revisited the questions surrounding the source and duration of the sun’s radiant heat (“On the Sun’s Heat”).  He concluded once more that the only possible explanation among known sources of energy is gravitational condensation, and that, “In the circumstances . . . it would, I think, be exceedingly rash to assume as probable anything more than twenty million years of the sun’s light in the past history of the earth, or to reckon on more than five or six million years of sunlight for time to come” (390).  It was the fact of limitation and secular mortality, however, not the odd one or ten million years in the death sentence, that, as the century drew to a close, depressed the spirits and stimulated the imagination to consider one’s end.[19]  Even Darwin, reflecting towards the end of his life on his present inability to summon up feelings that connect to a belief in God—and with it, immortality—could write with respect to the latter:

nothing shows me how strong and almost instinctive a belief it is, as the consideration of the view now held by most physicists, namely that the sun and all the planets will in time grow too cold for life, unless indeed some great body dashes into the sun and thus gives it fresh life.—Believing as I do that man in the distant future will be a far more perfect creature than he now is, it is an intolerable thought that he and all other sentient beings are doomed to complete annihilation after such long-continued slow progress. (Autobiography 92)[20]

If Thomson stuck to his guns well into the nineties and after, Huxley did not; and his qualms about a Spencerian gospel of progress, founded on evolutionary adaptation and competition, emerged, together with an acknowledgement of thermodynamic considerations for a species (our own) able to bring ethical consciousness to bear on the processes of nature.  The year was 1887, the impetus both public and personal, and Huxley’s metanoia is made vivid in the contrast between two invited performances: one, an essay on the fifty-year progress of science commissioned for the Jubilee volume, The Reign of Queen Victoria; the other, an address to a general Manchester audience entitled “The Struggle for Existence in Human Society.”

In the wide-ranging Jubilee essay on “Science,” Huxley names the three great achievements of an age unmatched in scientific attainment, all intimately connected, and each applicable to the whole physical cosmos: the doctrine (as he calls it) of the constitution of matter, the doctrine of the conservation of energy, and the doctrine of evolution.  His account of thermodynamic theory dwells only on the conservation law, though he attaches an ambiguous afterthought: “It follows that energy, like matter, is indestructible and ingenerable in nature.  The phenomenal world, so far as it is material, expresses the evolution and involution of energy, its passage from the kinetic to the potential condition and back again.  Wherever motion of matter takes place, that motion is effected at the expense of  part of the total store of energy” (361). The last sentence is as close as he comes to acknowledging the second law of thermodynamics, and (if so construed) there is no thought here beyond excluding possible recruitment from a source outside nature.[21]

The Jubilee year was also marked by much social and political unrest with, in the fall, mass meetings of the unemployed in London and clashes with the police.  Also that fall, after great suffering under the shadow of mental illness, Huxley’s talented and much loved daughter Mady died of pneumonia.  To stand helpless before such suffering, and to share it, while coming to see a mountain of misery as the fruit of industrial progress, can shake one’s confidence in nature’s plan.  A few weeks after Mady’s death, Huxley delivered on his promised address in Manchester, bending his talk, whose working title had been “Programme of Industrial Development,” into the first of a series of attempts to come to terms with “the apparent paradox that ethical nature, while born of cosmic nature, is necessarily at enmity with its parent” (viii).[22]  Forcefully ridiculing the argument that one can take comfort from the reflection that “the terrible struggle for existence tends to final good, and that the suffering of the ancestor is paid for by the increased perfection of the progeny,” he points out that it is an error to imagine that evolution signifies a constant tendency to increased perfection. Rather it involves a constant remodeling through adaptation to new conditions, whatever they are, so that:

Retrogressive is as practicable as progressive metamorphosis.  If what the physical philosophers tell us, that our globe has been in a state of fusion, and, like the sun, is gradually cooling down, is true; then the time must come when evolution will mean adaptation to an universal winter, and all forms of life will die out, except such low and simple organisms as the Diatom of the arctic and antarctic ice and the Protococcus of the red snow.  If our globe is proceeding from a condition in which it was too hot to support any but the lowest living thing to a condition in which it will be too cold to permit of the existence of any others, the course of life upon its surface must describe a trajectory like that of a ball fired from a mortar; and the sinking half of that course is as much a part of the general process of evolution as the rising. (“Struggle” 198-9)

Huxley assigns neither length nor velocity to his trajectory, since in fact his concern is in the present: with the world of competing industrial states where, among a vast mass of people in every European manufacturing city of any size, “la misère reigns supreme”; where many more are poised on the edge; and where, “with every addition to the population, the multitude already sunk in the pit and the number of the host sliding towards it continually increase.” He does not believe that societies “in which the elements of decomposition are thus swiftly and surely accumulating can hope to win the race of industries” (216).  He holds to the inevitability of a Darwinian, indeed Malthusian competition between industrial societies, but challenges the need for starvation wages, and warns that where a given social order plainly makes for evil and not for good, men will think it high time to begin a fresh experiment; and “animal man, finding that the ethical man has landed him in such a slough, resumes his ancient sovereignty, and preaches anarchy; which is, substantially, a proposal to reduce the social cosmos to chaos, and begin the brute struggle for existence once again” (215).

If Kelvin, a deeply religious man, while insisting upon the integrity of scientific law with unqualified rigor, keeps a card up his sleeve: the inscrutable character and unforeclosed possibility of divine agency,  Huxley here puts his cards on the table: the ethical imperatives, in the face of the indifferent operations of scientific law, upon human agency.  Kelvin never found occasion to admit a dissonance between his faith and the science that uncovered the mechanical operations of God’s works.  Huxley, unlike some of his contemporaries and successors, declines the option of making a substitute religion of Science (or Art), but in arriving at the existential divide whereby “ethical nature, while born of cosmic nature, is necessarily at enmity with its parent,” articulates an alienation that belongs to the modern world.[23]

Martin Meisel is the author of Realizations: Narrative, Pictorial, and Theatrical Arts in Nineteenth-Century England (1983) and How Plays Work (2007).  He is currently readying for publication a book on the imagination and representation of Chaos.



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—. “Preface.” Collected Essays: Evolution & Ethics and Other Essays. Vol. 9. London: Macmillan, 1903. v-xiii. Print.

—. “Science.” The Reign of Queen Victoria: A Survey of Fifty Years of Progress. Ed. Thomas Humphry Ward. Vol. 2. London: Smith, Elder & Co., 1887.  322-87. Print.

—. “The Struggle for Existence in Human Society.”  Collected Essays: Evolution & Ethics and Other Essays. Vol. 9. London: Macmillan, 1903. 195-236. Print.

Kant, Immanuel. Universal Natural History and Theory of the Heavens, or Essay on the Constitution and the Mechanical Origins of the Entire Edifice of the Universe, Treated in Conformity with Newtonian Principles. 1755. In Kant’s Cosmogony. 1900. Ed. & trans. W. Hastie. New York: Greenwood, 1969. Print.

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—.  “Outlines of the Science of Energetics.” Miscellaneous Scientific Papers. London: Charles Griffin, 1881. 226-27. Print.

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—. “Of Geological Dynamics.” Popular Lectures and Addresses. Vol. 2. London and New York: Macmillan, 1894. 73-113. Print.

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[1] First read in Belfast before the British Association on 2 September 1852, and first published in the November 1852 volume of the Philosophical Magazine. Rankine would make notable contributions to energy theory, including the distinction between “potential energy” (his coinage) and “actual energy” (soon rechristened “kinetic”).  His “thermodynamic function,” a measure of transformation, has much in common with Clausius’s “entropy.”

[2] Kant, a formidable scientific thinker early in his career, duly credited among other things with developing the Nebular Hypothesis (along with Laplace), gave fullest expression to his cosmology in his Universal Natural History and Theory of the Heavens, which was first printed in 1755 but subsequently impounded for a decade.

[3] The science Rankine here names “Energetics” developed into a powerful view on the nature of physical reality later in the century, with consequences in Einstein’s mass-energy equation.

[4] From a lecture delivered in Königsberg, 7 February 1854, commemorating Immanuel Kant.

[5] From a lecture delivered at Frankfort on 23 September 1867. The bleak power of an inexorable death of the universe inscribed in its fundamental physical laws has never quite faded from science or imagination, though the writ and run of the Second Law has been more than once challenged (e.g. by Popper, in “Irreversibility; or, Entropy since 1905”), and sometimes been effectively sidelined by aspects of contemporary speculative cosmology.  For a thorough, conscientious attempt to take account of what was known (as of the end of the twentieth century) that bears on the issue, embracing astrophysics and particle physics, and possible scenarios under a “closed,”  “nearly flat,” and “open” universe, see Fred C. Adams and  Laughlin.

[6] From Epicurus’s own summary of his doctrine, as given by Diogenes Laertius in Lives of the Eminent Philosophers. Diogenes reports the story that Epicurus “turned to philosophy in disgust at the schoolmasters who could not tell him the meaning of ‘chaos’ in Hesiod” (531-32).

[7] Dated 20 September 1778, Franklin first published the piece from his own press at Passy in French translation.  It appears (finely illustrated) as “Dernière paroles d’un ephémere” in Grandville’s Scènes de la vie privée et publique des animaux.

[8] See Roger, Buffon: A Life in Natural History,  386-87, summarizing Buffon’s “First View of Nature” (1764).  Buffon later became convinced that the earth depended for its climate and habitability on its own internal heat, and calculated the rate of its dissipation for the earth and other bodies in the solar system in the context of his History of Minerals in 1774 (“Partie hypothèque. Premier memoire. Recherches sur le refroidissement de la terre et des planètes.”)  It was the cooling of the earth, rather than any diminution of the sun, that would bring on its eventual refrigeration; by which time a larger planet like Jupiter would have cooled into habitability.

[9] The prose passage is from a vivid letter to Thomas Love Peacock dated 24 July 1816, first published in Mary Shelley’s History of a Six Weeks’ Tour through a Part of France, Switzerland, Germany and Holland, 156-163.

[10] Byron’s debt here to the end of the Dunciad is evident. Robert  M. Adams connects the poem, via Shelley, to Buffon’s projection of progressive glaciation (201).  However, the immediate suggestion for the poem (dated July 1816) is likely to have been the worldwide effects of the eruption of Tambora in Indonesia in 1815, which gave Europe in 1816 the coldest (and probably darkest) summer on record, and produced crop failures everywhere (See Henry and Elizabeth Stommel, Volcano Weather: The Story of 1816, the Year without a Summer).  The poem is invoked for its inspired prescience in Stoppard’s double-time masterpiece,  Arcadia (1993), where entropy, and its palliative, complexity (also called “Chaos”), capture the scientific imagination of some of his early nineteenth-century characters.

[11] In Britain, there were six editions in two translations between 1813 and 1829.   Cuvier gave a later version  of this introductory treatise separate publication in France also, as  Discours sur les révolutions de la surface du globe. 

[12] Byron’s complex ironies—lost in the scandal Cain evoked—are given their due in O’Connor’s wide-ranging The Earth on Show (102-104).  O’Connor explores the ferment of geological argument and exposition during the half century, and its expression in a plethora of popular vehicles, textual and spectacular.

[13] For a comprehensive account of the developments in geology as a science during this period, and notably,  its reshaping as a historical discipline,  see Rudwick’s Bursting the Limits of Time and Worlds before Adam.

[14] Both passages quoted from Hutton’s The Theory of the Earth (1795) in Huxley’s Presidential Address to the Geological Society (1869), “Geological Reform.”

[15] Darwin had already dropped the passage on the denudation of the Weald with its estimates (from Chapter IX of On the Origin of Species) in his third edition (1861), having been convinced of its inaccuracies by an article in the Saturday Review (24 December 1859). Thereafter he took care to let others argue the details on the temporal parameters.

[16] The role played by Thomson’s religion in shaping his science is fertile ground for argument. In their incisive and authoritative biographical study of Kelvin, Energy and Empire, Smith and Wise establish its importance in Kelvin’s mind and thought; and in his solo performance, The Science of Energy: A Cultural History of Energy Physics in Victorian Britain, Smith further argues that the formative climate of Presbyterian religion, Clydeside marine engineering, and an ingrained antipathy to waste operated decisively among the largely Scottish, status-conscious cluster of scientists—led by Thomson—who developed thermodynamic theory in Britain.  It is certainly plausible that, for example, a Calvinist rigor infused Thomson’s formulation of the First and Second laws and the predestinate trajectory implied in the Second; and it is more or less evident that his antipathy to mindless process as opposed to purposeful order roused his combative instincts in the face of Darwinian naturalism.  But as far as energy physics itself goes, one should be mindful of the caution advanced by Thomson’s fellow North Briton, Adam Smith, in the previous century, on “The Principles which Lead and Direct Philosophical [i.e. scientific] Enquiries,” where Smith expresses considerable skepticism towards the practice of applying systems originating in one sphere of discourse to phenomena belonging to another (46-47).  In any case, Thomson rarely appealed to principles or beliefs external to the structures of science and insisted on the integral and indeed preemptive authority of scientific reasoning.

[17] In the interval, Thomson had read a note to the Royal Society of Edinburgh (18 December 1865) titled, “The ‘Doctrine of Uniformity’ in Geology Briefly Refuted,” using the heat lost from the earth.

[18] Thomson’s failure to leave room for the possible effects of sub-crustal convection—which he well understood in other contexts—is a different matter.  See Richter, “Kelvin and the Age of the Earth.”  Richter sums up:

The original problem was to determine the age of the earth from a thermal model.  The subsequent discovery of radioactivity completely changed the subject, not so much because of the associated heat production, but because it gave a separate and different measure of the age of the earth.  The modern problem is almost the reverse of the original: given the great age of the earth one seeks a thermal and dynamical model that can account for its present thermal state.  Such a model must take account of not only radiogenic heat but also the role of mantle convection as a means of exploiting the entire heat content of the earth. (401)

[19] See, for example, Flammarion’s La Fin du Monde (1894), a scientifically grounded  fantasy by an astronomer and science popularizer, widely read and translated, that combines both catastrophist (a brush with a comet) and long term entropic scenarios (serialized in America [1893] as Omega: The Last Days of the World); and Wells’s seminal work of science fiction, The Time Machine (1895), which combines both evolutionist and thermodynamic scenarios for its projections of human, bioform, secular, and solar decline.

[20] Written 1876; first published 1887.

[21] Later in the essay, Huxley notes that “attempts have been made, by the help of deductions from the data of physics, to lay down an approximate limit to the number of millions of years which have elapsed since the earth was habitable by living beings.  If the conclusions thus reached should stand the test of further investigation, they will undoubtedly be very valuable. But, whether true or false, they can have no influence upon the doctrine of evolution in its application to living organisms” (366).

[22] From the preface to Evolution & Ethics and Other Essays. For the contexts, personal and public, see Desmond, Huxley: Evolution’s High Priest (176-9). Desmond describes the published version of Huxley’s lecture (Nineteenth Century [January 1888], 194-236) as much toned down.

[23] For an overview both compact and wide-ranging, including many of the scientific matters pursued above, see Brush, “The Nebular Hypothesis and the Evolutionary World View,” and Gillian Beer’s classic essay, “The Death of the Sun.” The best account of Kelvin’s intervention remains Burchfield’s Lord Kelvin and the Age of the Earth.  Burchfield underlines Kelvin’s accomplishment—that is, his positive effect on geology and geologists of the next generation with respect to quantitative sophistication and reduced parochialism.