Lord Kelvin’s Core Values Defended

Myth: Lord Kelvin held back the progress of geology for 100 years by insisting the Earth was younger than geologists and evolutionists believed, but his model was refuted when radioactivity was discovered.  Fact: Radioactivity made no difference to Kelvin’s claims, and he was an exemplary scientist who rectified bad practices among geologists.  That’s the upshot of a claim that was made, criticized, then defended in the GSA Today, a publication of the Geological Society of America.^1,2,3

William Thomson, Lord Kelvin (1824-1907). Click for biography.

Last January (2007),¹ Philip England (Oxford), Peter Molnar (U of Colorado) and Frank Richter (Dept. of Geophysical Sciences, Chicago) wrote an iconoclastic piece defending Lord Kelvin.  William Thomson, later referred to as Lord Kelvin, has had a patchy reputation among modern scientists.  In his day, the physicist of Glasgow was the most eminent scientist in the British Isles (see online book).  Even Mark Twain confessed, “As Lord Kelvin is the highest authority in science now living, I think we must yield to him and accept his view.”  But between his many accomplishments and honors, he also made enemies – especially among geologists.

One of his most controversial views was that the Earth’s heat output (and that of the sun) proved it could not be older than 100 million years.⁴  In the 20th century, Kelvin’s reputation suffered.  According to England et al, a myth arose that his claims about a young earth were overturned by the discovery of radioactivity:

We are left with the question as to why the myth persists that the discovery of radioactivity simultaneously proved Kelvin wrong and provided the explanation for his error.  Part of the answer, perhaps, is that it makes a good story.  Rutherford’s biographer (Eve, 1939) reports that he repeated his tale of thinking on his feet in front of the “old bird” Kelvin on many occasions; it is entirely possible that the pleasing form of the anecdote, and the eminence of its author, led to the uncritical acceptance of the myth.  As Stephen Gould (who himself propagated this myth) wrote: “The most erroneous stories are those we think we know best—and therefore never scrutinize or question” (1996).  It is hard to dissuade aging scientists, as they slip into their anecdotage, from repeating stories that they find amusing, but their younger colleagues must not mistake such stories for the history of science.

(Let our elderly readers take relief in that they said anecdotage, not dotage.)  Kelvin has also been pictured as somewhat of a bombastic figure inserting his physicist views into geology where they didn’t belong:

The story of Kelvin and the age of the Earth is often told as a David-and-Goliath struggle, with the geologists in the role of the underdog armed only with the slender sword of geological reasoning, while Lord Kelvin bludgeoned them with the full force and prestige of mathematical physics.  Kelvin’s come-uppance is often taken as evidence that simple physics ought not to be applied to geological problems, but there have been numerous occasions when simple physical models have had great explanatory power in geology.

The authors wrote to set the historical record straight.  It is not that they agree with his age estimate – not at all.  They affirm modern estimates to the tune of billions of years.  Kelvin was wrong, they wrote, not because of radioactivity, and not because his equations and calculations were erroneous, or because he was out of his field, but because his assumptions about the thermal structure of the Earth were questionable.  They described how one of Kelvin’s former assistants, John Perry, showed that the earth could sustain its heat for two billion years by convection if one assumed a firm crust and a liquid interior.  This had nothing to do with the discovery of radioactivity, which they said made no difference to Kelvin’s model.  The heat contribution from radioactivity was negligible; “consequently—even if Kelvin had included radioactive heat in his calculation—his estimate of the age of the Earth would have been unaffected.”

While exonerating Kelvin of errors in his physics, mathematics and modeling, the authors also defended his reputation as a great scientist.  Some historians have tended to focus on some blunders Lord Kelvin made and predictions that did not come true.  England et al. give good press to the Scottish physicist.  They defended his use of physical models and equations.  They defended his explicit mention of his assumptions behind his models.  They defended his corroborating one conclusion (the age of the Earth) with another (the age of the sun).  They praised his use of thermodynamics, and they defended his scientific restraint in a milieu of hot air and passionate rhetoric.  Kelvin himself in 1899 “cites many examples of rhetoric from his opponents and, while Kelvin himself was generally quite measured in his replies,” they said.  His view on the age of the Earth fell into disfavor not due to any failings as a scientist, but because “all simple models are bound to fail, and we may learn as much by their failure as by their successes.”

The ones who don’t come out smelling like a rose in this paper are the geologists of Kelvin’s day.  England, Molnarb and Richter described how they were under the spell of Lyell and Hutton:

The early nineteenth-century formulation of Uniformitarianism was commonly expressed through Hutton’s aphorism, “No vestige of a beginning, no prospect of an end.”  The doctrine that the Earth was of unlimited age allowed geologists to explain any phenomenon not by the laws of physics, but by “reckless drafts on the bank of time” (Chamberlin, 1899).  For Kelvin, this game without rules was simply not scientific; indeed, it was forbidden by the laws of thermodynamics, which he had played such a large part in developing.

Kelvin was good for geology, they explained, because he forced them to deal with the realities of physics.  Thermodynamics proved the Earth had a finite age.  Lazy geologists, accustomed to infinite resources in the bank of time, needed to get real.  Kelvin forced them to realize that “quantitative reasoning was a crucial part of geological endeavor.”⁴  But have the lessons been learned?  They quipped that today’s geologists, by recklessly assuming inexhaustible heat from radioactivity, have merely changed banks: “In other words, Chamberlin’s ‘reckless drafts’ were now on the bank of heat, rather than on the bank of time.”

Criticizing geologists in a geological journal may not have been the better part of discretion.  This month, two geologists seemed to take umbrage at this rehabilitation of Kelvin.²  Hofmeister and Criss from Washington University of Missouri said, “In touting John Perry, England et al. (2007) misrepresent modern and historical efforts to understand Earth’s cooling.”  They took issue with numbers England et al. gave for thermal conductivity and convection, and also pointed to “Kelvin’s fundamental error of using equations inappropriate” for cooling of the Earth.  They disagreed with the insufficiency of radioactivity as a heat source.  Then, they ended with this stinger: “Kelvin’s famous calculations, coupled with denial of observational data, impeded geoscience for ~100 yr.  It is a shame to see data ignored and Perry lionized given his statement ‘I dislike very much to consider any quantitative problem set by a geologist.’”

England et al struck right back.³  “In touting their views, Hofmeister and Criss (2007) misrepresent what we wrote, what Perry wrote, and some simple aspects of heat transfer.”  After defending the technical points, they got to the personal matters of character and reputation:

Their final paragraph is purely rhetorical.  Kelvin did not ignore observations; indeed, his attempts to use observations to constrain the age of the Earth forced geologists to abandon their reckless drafts on the bank of time.  Hofmeister and Criss’s dismissal of this history as Kelvin’s “impeding geoscience for ~100 years” is not supported by serious work on the matter.  Furthermore, their attack on Perry shows a complete misunderstanding of a modest and conciliatory person.  Perry’s reluctance “to consider any quantitative problem set by a geologist” should be taken as an expression of qualms about his ability to combine geology and physics, not as hubris.

¹Philip England, Peter Molnar, Frank Richter, “John Perry’s neglected critique of Kelvin’s age for the Earth: A missed opportunity in geodynamics,” GSA Today, Volume 17, Issue 1 (January 2007), pp. 4-9, DOI: 10.1130/GSAT01701A.1.
²Anne M. Hofmeister, Robert E. Criss, Comment on England et al, GSA Today, Volume 17, Issue 7 (July 2007), p. 10, DOI: 10.1130/GSAT01707C.1.
³Philip England, Peter Molnar, Frank Richter, REPLY to Hofmeister and Criss, GSA Today, Volume 17, Issue 7 (July 2007), p. 11, DOI: 10.1130/GSAT01707R.1.
⁴They recounted a conversation Kelvin had with an old-earth geologist, who said, “I am as incapable of estimating and understanding the reasons which you physicists have for limiting geological time as you are incapable of understanding the geological reasons for our unlimited estimates.”  Kelvin gave him the memorable retort, “You can understand the physicists’ reasoning perfectly if you give your mind to it.”
⁵Working through Kelvin’s equations, they said, “…this gradient yields an age of 96 Ma; Kelvin (1863a) gave bounds of 24 Ma and 400 Ma on the age to take account of uncertainties in thermal gradient and thermal conductivity.”  Kelvin used his calculations as an upper limit for the age of the Earth.  This should not imply that he believed it was actually that old.  This upper limit wreaked havoc among the Darwinians who needed much more time to evolve their tree of life, because at best, it is less than 1/10 the geologists’ assumed age of the Earth; at worst, 1/200.  This “odious spectre” caused Charles Darwin and his disciples extreme stress (02/02/2004 commentary).  In desperation, they tried to find workarounds to the clear scientific constraint Kelvin had imposed.  It forced Darwin to try to speed up the evolutionary process with Lamarckian mechanisms.  Darwin died before radioactivity was discovered, but the evolutionists jumped on it as the answer to Kelvin.  That was undoubtedly part of the reason it became a myth that few questioned with the kind of mathematical and physical rigor that marked Kelvin’s reputation (for a recent example, see Adam Kirsch in the New York Sun assuming radioactivity answered Kelvin, and the Bible).  It is notable, therefore, that England et al. here dismiss radioactivity as a cure-all for the heat problem.

What a colorful phrase—“reckless drafts on the bank of time.”  Doesn’t that describe the banking habits of evolutionary biologists and geologists still today?  They think long ages provide a blank check for any miracles they need.  It was good for these three men to set the record straight.  Kelvin was not perfect, but he was a heck of a lot better scientist than many geologists of his day and thereafter who speculate with utter disregard for the realities of thermodynamics.  Unless someone holds them accountable, these reckless check writers will continue to commit fraud via time laundering and heat laundering.

Pay attention to footnote 4 above: “You can understand the physicists’ reasoning perfectly if you give your mind to it.”  Kelvin was a Christian with a high regard for the Bible (see footnote 5 above), but notice how he appealed to his colleagues’ scientific integrity, not to religious arguments, to challenge the Darwinian revolution that was in full gear at the time.  That’s still an effective strategy in today’s debates against materialistic pseudoscience.  We need more Lord Kelvins.