The age of the Earth-12: The final synthesis

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series on the age of the Earth, see here.

The minimum age of the Earth kept getting pushed back as older rocks kept being found and methods of analysis improved with the invention of new instruments such as the mass spectrometer. The minimum age was raised to 1.90 billion years in 1935, 3.35 billion years in 1947, to 3.45 billion years in 1956.

But there arose a new problem. Astronomers had discovered that the universe was expanding and Edwin Hubble’s (1889-1953) discovery of the law now associated with his name enabled scientists to estimate the time when the universe would have begun, and they initially arrived at an age of 1.80 billion years (Jackson, p. 251). It was absurd to suppose that the universe was younger than the Earth and this caused some consternation. But as the reach of telescopes increased and greater and greater expanses of the vastness of the universe came under observation, the calculated age of the universe kept increasing, to 10 billion years by the early 1950s, to 13 billion years by 1958, and finally to the present value of 13.7 billion years. Thus the potential paradox of the universe being younger than the Earth was resolved.

To obtain the age of the Earth we would need to find rocks that were formed at the time of the Earth’s formation. But the problem with finding those rocks is that plate tectonics would likely have crushed most of them and so they are not easy to obtain. Despite this, determined efforts have steadily unearthed older and older rocks. According to the US Geological Survey:

The oldest rocks on Earth found so far are the Acasta Gneisses in northwestern Canada near Great Slave Lake (4.03 Ga) and the Isua Supracrustal rocks in West Greenland (3.7 to 3.8 Ga), but well-studied rocks nearly as old are also found in the Minnesota River Valley and northern Michigan (3.5-3.7 billion years), in Swaziland (3.4-3.5 billion years), and in Western Australia (3.4-3.6 billion years)… In Western Australia, single zircon crystals found in younger sedimentary rocks have radiometric ages of as much as 4.3 billion years, making these tiny crystals the oldest materials to be found on Earth so far. The source rocks for these zircon crystals have not yet been found.

The final major shift in the age of the Earth came when Clair Patterson (1922-1995) studied the age of meteorites that had crashed to the Earth. It was assumed that these meteorites were formed at the same time as the Earth and the solar system but since they arrived here much later were less likely to be contaminated by the ebbs and flows of Earth’s geological history. Patterson studied two samples from the Canyon Diablo meteorite that fell in Arizona about 50,000 years ago and reported in 1953 that their ages were 4.510 and 4.570 billion years. More and more meteorites from all over the globe started to be analyzed and the ages were all consistent and converged to 4.550 billion years. The oldest moon rocks have been measured to be between 4.4 and 4.5 billion years old, which is consistent with the other dates.

So that is where we are today, with the age of the Earth determined to be 4.55 billion years, with an uncertainty of about 1%.

The search for the age of the Earth is truly a remarkable story. There are many lessons that the search can teach us but the one that I want to pick out to end this series of posts is how the desire for consistency among the fields of geology, paleontology, chemistry, physics, biology, and astronomy all played a role. One of the consequences of this search has been the intermeshing of these fields, theories in one being interwoven with theories in the others. It is this interconnectedness that gives strength to the conclusions.

Those people who think the Earth is 6,000 years old are living intellectually in a time before the Enlightenment. It is not simply that the value they have for the age of the earth is wrong, even absurdly so. It is that they think they are living in a time when facts were largely isolated things that could be accepted or rejected individually. This is no longer true. Nowadays a scientific ‘fact’, although identified with one particular field, is the product of a large network of theories encompassing many fields that were once separate. To get an authoritative answer to the question of the age of the Earth you would probably go first to someone identified as a geologist, but her answer will not be the product of just geological research but of a whole complex of theories that spread far and wide. To reject such a fact without exploring the consequences it has for all the other elements that went into its production is to reject science altogether.

Pierre Duhem, one of the earliest people who spoke about the interconnectedness of science, captured this beautifully in a metaphor comparing how a watchmaker and doctor operate:

People generally think that each one of the hypotheses employed in physics can be taken in isolation, checked by experiment, and then, when many varied tests have established its validity, given a definitive place in the system of physics. In reality, this is not the case. Physics is not a machine which lets itself be taken apart; we cannot try each piece in isolation and, in order to adjust it, wait until its solidity has been carefully checked. Physical science is a system that must be taken as a whole; it is an organism in which one part cannot be made to function except when the parts that are most remote from it are called into play, some more so than others, but all to some degree. If something goes wrong, if some discomfort is felt in the functioning of the organism, the physicist will have to ferret out through its effect on the entire system which organ needs to be remedied or modified without the possibility of isolating this organ and examining it apart. The watchmaker to whom you give a watch that has stopped separates all the wheelworks and examines them one by one until he finds the part that is defective or broken. The doctor to whom a patient appears cannot dissect him in order to establish his diagnosis; he has to guess the seat and cause of the ailment solely by inspecting disorders affecting the whole body. Now, the physicist concerned with remedying a limping theory resembles the doctor and not the watchmaker. (my italics)

Duhem wrote this in 1906 in his book The Aim and Structure of Physical Theory. I do not think it a coincidence that this was the very period when convergence of scientific theories was occurring.

(Main sources for this series of posts are The Chronologers’ Quest: The Search for the Age of the Earth (2006) by Patrick Wyse Jackson and Lord Kelvin and the age of the Earth by Joe D. Burchfield (1975).)

POST SCRIPT: There’s a Jesus on a spring?

<td style='padding:2px 1px 0px 5px;' colspan='2'Teapocalypse – The Tea Party Split
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The age of the Earth-11: The Earth becomes very old again

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series on the age of the Earth, see here.

The discovery of radioactivity and the associated concept of half-lives of elements opened up the possibility of determining the absolute age of rocks. This argument was developed by Bertram Boltwood in the very early 1900s and is the process now referred to as radiometry (Jackson, p. 237). The argument goes like this. Suppose a sample of rock is found to contain 100 grams of a parent radioactive material P and 300 grams of the stable final daughter element D in its radioactive series, and also suppose that the half-life of this decay has been measured to be 10 years. If we assume that the rock initially had only the parent element P and no D, then we can assume that rock sample initially had 400 grams of P, then after 10 years, it had 200 grams of P and 200 grams of D, then after another 10 years, it would have 100 grams of P and 300 grams of D, and so on. Hence the rock must have been formed 20 years ago.

The more general formula for calculating the age of a rock is age=(half-life)xlog2(1+Dnow/Pnow), where Pnow is the measured amount of the parent radioactive element in the sample at the current time and Dnow is the amount of the final stable daughter element.

Of course, nothing is that simple in real life. Apart from all the difficulties in finding and measuring the properties of rocks, an obvious complicating factor is that some of the parent and daughter elements may have escaped or entered the sample, which is a real possibility during the time that the rock was molten before it solidified. The effect of this can be corrected for by the method of isochron dating, which I will not get into here but the link gives a very clear discussion. In addition, if there are many different radioactive series with multiple elements and multiple rocks involved, and their results converge around a single age, that lends further confidence to the result.

Now that the absolute ages of rocks could be determined, that meant that scientists could determine the absolute ages of the various geological layers in the Earth’s crust (that were formed by sedimentation) in addition to their relative ages. They did this by measuring the ages of the igneous rocks that were formed by volcanic activity that created molten rocks that cooled and are now buried in those layers. This provides an additional measure of the ages of the fossils that are found in those layers.

Apart from all this valuable information about the absolute ages of geological layers and fossils that were now possible to determine, the race was also on to find the oldest rocks on the planet, because those would set a lower bound on the age of the Earth.

Lord Rayleigh in 1905 found rocks that were 141 million years old and shark’s teeth that were 77 million years old. In 1907, Boltwood published the ages of mineral specimens that ranged from 400 million to 2.2 billion years (Jackson, p. 237). Such results would have been unthinkable just ten years earlier. The fact that these figures were now not summarily rejected shows how rapidly views had changed.

These much larger times were not uncritically accepted, however. Oddly, some critics were from the field of geology itself. Those who had got used to developing their theories to accommodate a 100 million year old Earth and had resisted efforts to lower it to 20 million, were now disconcerted by the much larger times that were now being suggested. Critics charged that we could not know that the half-lives of radioactive elements had remained the same through all time. Maybe they used to decay faster in early days, misleading us as to their ages.

But as more research was done, these objections began to disappear, and soon other methods (such as the presence of what are known a pleochroic halos in some materials) led to estimates of ages of rocks that were also in the hundreds of millions of years.

Geologist Arthur Holmes (1890-1965) produced a time scale in 1911 based on the rocks found in various geological strata and produced dates for the Carboniferous (340 million years), Devonian (370 million years) and Silurian (430 million years) eras, values that hold up remarkably well when compared with current values of 360, 416, and 444 million years respectively (Jackson, p. 245). Interestingly, the record for the oldest rocks at that time produced by Holmes were from my country of origin Sri Lanka (then called Ceylon), which were 1.64 billion years old.

It is often pointed out, correctly, that scientists can dogmatically cling on to their theories even in the face of contrary evidence. As Max Planck said, “A new scientific truth does not triumph by convincing its opponents and making them see the light, but rather because its opponents eventually die, and a new generation grows up that is familiar with it” (Burchfield, p. 165). The deep reluctance to accept the new paradigm may be restricted to only those scientists who, like Kelvin and the age of the Earth, have invested a lot of their own time and prestige in working with the old paradigm. It is often the case that the scientific community as a whole changes its views faster than individual scientists.

The age of the Earth is a case in point. A little over a decade after the discovery of radioactivity, and just four years after Kelvin died unconvinced that the Earth was more than tens of millions of years old, there was no doubt anymore that the Earth was really and truly old, in the billions of years. It was a momentous change in thinking occurring over a remarkably short time, showing how science goes where the evidence leads even if individual scientists resist the changes.

(Main sources for this series of posts are The Chronologers’ Quest: The Search for the Age of the Earth (2006) by Patrick Wyse Jackson and Lord Kelvin and the age of the Earth by Joe D. Burchfield (1975).)

POST SCRIPT: The grand old traditions

It’s time once again to declare war on Christmas.

<td style='padding:2px 1px 0px 5px;' colspan='2'The Blitzkrieg on Grinchitude – Treesus & CHRIST-mas Tree
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The age of the Earth-10: The revolutionary impact of the discovery of radioactivity

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series on the age of the Earth, see here.

The dawn of the 20th century was an extraordinary time of ferment in science. In the case of physics, in addition to the turmoil over the age of the Earth, there was also the well-known crisis that the newly emerging models of the atom as a tiny positively charged nucleus and orbiting negative charges seemed to contradict the well-established theory of electrodynamics. Another crisis was that the ‘luminiferous ether’, the material believed to permeate all space and the carrier of light waves, seemed to be extraordinarily successful in evading all attempts at detecting its presence or its properties. In addition, the blackbody radiation spectrum seemed to defy understanding on the basis of what were thought to be well-established laws of mechanics and radiation.

But that same period also produced one major scientific revolution after another. 1900 saw the re-discovery of Mendel’s theory of genetics that showed that the heritable qualities we had were stored in our bodies in discrete units that were passed on intact to our progeny, and not blended away on breeding as previously thought, thus removing one major objection to natural selection. The full integration of Mendelian genetics with natural selection into what is now known as the neo-Darwinian synthesis was, however, not fully understood until around 1920, with the full flowering of the field of population genetics.

1900 also saw the introduction by Max Planck (1858-1947) of the quantum hypothesis that seemed to explain the blackbody radiation anomaly. 1905 saw the emergence of Albert Einstein (1879-1955) and his theory of relativity that made the ether redundant and dispensable, thus solving the mystery of why it had seemed so elusive. That year also saw the publication of a second paper by Einstein which contained the result that is now famously written as E=mc2. 1913 saw the introduction by Niels Bohr (1885-1962) of the planetary model of the atom, the first step in resolving the contradictions between the new atomic theory and electrodynamics.

But as far as the age of the Earth was concerned, the major discoveries that impacted it was the discovery of X-rays in 1895, followed rapidly by the discovery of the alpha, beta, and gamma radiation of radioactivity. There began a rush to isolate the elements that produced this extraordinary new radiation and to measure their properties. Marie (1867-1934) and Pierre (1859-1906) Curie were among the leaders of the quest in isolating these elements and soon the list contained actinium, uranium, polonium, thorium, and radium.

The key discovery that had relevance for the age of the Earth was the discovery in 1903 by Pierre Curie that radium emitted prodigiously large amounts of heat. An early calculation that same year showed that a mere 3.6 grams of radium per cubic meter would be sufficient to be the source of energy radiated by the Sun (Burchfield, p. 166). Since radium existed in the Earth, people immediately realized that if this heat did not have its origins in gravitational or mechanical or chemical energy (and it soon became clear that it did not and was instead due to the mass to energy conversion discovered by Einstein.), then this meant that there was a source of constant heat generation that had not been previously taken into account.

Since there was no way to determine how much heat was continually being produced in the deep interiors of the Earth by all the radioactive elements there, the old calculation methods of Kelvin and other physicists, who assumed that all the Earth’s heat was created at its formation and that the Earth could subsequently be treated as a strictly cooling body, had to be discarded. Furthermore, since there was no longer any method of determining the absolute age of the Earth, the desire of the geologists and paleontologist and natural selectionists for long ages could be accommodated. Too bad that Darwin did not live to see it.

But while radioactivity completely undermined the older methods for determining the age of the Earth, it at the same time gave birth to a new and far more accurate method.

It was Ernest Rutherford (later Lord Rayleigh, 1871-1937) who, with others, was associated with some of the key conceptual breakthroughs involving radioactivity, such as realizing that during radioactive decay, one element became transformed into another, which in turn was transformed into another, and so on until a stable element was reached, at which point the process stopped. He was the one who discovered that if you take a sample of radioactive material, the time taken for the initial amount of material to decay to half its original value was a fixed amount (known as its ‘half-life’) that is independent of the amount of material you started with.

So if you started with (say) 160 grams of some radioactive element that had a half-life of (say) 10 days, then after 10 days you would have 80 grams left, then after 20 days (i.e. another 10 days) you would have 40 grams left, after 30 days, you would have 20 grams left, and so on, with corresponding increases in the amount of the products created by the decay. What was to prove highly significant and useful was that each radioactive element had its own signature value of half-life and there was a huge range of half-lives for the different radioactive elements, ranging from fractions of seconds to hundreds of millions, even billions of years.

This discovery proved to be the key to finally unlocking the secret of the age of the Earth.

(Main sources for this series of posts are The Chronologers’ Quest: The Search for the Age of the Earth (2006) by Patrick Wyse Jackson and Lord Kelvin and the age of the Earth by Joe D. Burchfield (1975).)

POST SCRIPT: The Daily Show on Americans going to Mexico for health care.

<td style='padding:2px 1px 0px 5px;' colspan='2'American Refugees Seek Health Care in Mexico
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The age of the Earth-9: Biologists join the geologists against the physicists

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series on the age of the Earth, see here.

In the case of biology, Darwin’s theory of natural selection had been in retreat during the latter half of the 19th century under the assaults of both physicists and some biologists. Fleeming Jenkin (a physicist, engineer, and collaborator of Kelvin) had, in a review of Origins, delivered a severe critique of Darwin’s theory. He pointed out that not only was the time available insufficient for natural selection to work, but that the then-dominant theory of ‘blending inheritance’ (which said that children had a mixture of the qualities of their parents) worked against Darwin’s theory, since even if one parent experienced an advantageous mutation, that person’s child would only have half of it because the other parent would not have it, the grandchild one-fourth, and so on. The mutation would thus get diluted and disappear over time, and not grow and dominate the population, as natural selection argued.

Darwin had in fact already anticipated this difficulty and pre-emptively suggested that if the mutation occurred in several people and they mated with each other, then the dilution of the advantage would not occur and the population could grow. But he knew this was a weak argument. As a result, by 1880 Darwin was yielding somewhat on natural selection, saying that he had never argued that it was the only mechanism at work, which was true. He had always allowed for some Lamarckian influence though he was not fond of the idea. He now started giving greater room for Lamarckian mechanisms than he had done in the past.

But he was still hopeful that natural selection would eventually weather the storm caused by the short time scales, and that new understanding about the physics of the Earth and the rate of species change physics might vindicate his theory. Writing in his final published statement on the topic he said:

With respect to the lapse of time not having been sufficient since our planet was consolidated for the assumed amount of organic change, and this object, as urged by [Lord Kelvin], is probably one of the gravest as yet advanced, I can only say, firstly that we do not know at what rate species change as measured in years, and secondly that many philosophers are not yet willing to admit that we know enough of the constitution of the universe and of the interior of our globe to speculate with safety on its past duration. (Burchfield, p. 79)

When Darwin died in 1882, he was widely mourned as a great scientist who had convinced the world that the theory of evolution is a fact from which there is no going back. But the vindication of his theory of natural selection had to wait another thirty years.

In the previous post, I said that by the end of the 19th century, geologists had started balking at the ever-reducing ages of the Earth coming out of physicists calculations, most of the latter based on thermal cooling models developed by Kelvin and going back to Buffon. They felt that 100 million years was as far as they were willing to go. Some physicists were also starting to question Kelvin’s models and the values of the thermodynamic parameters on which his calculations depended.

Biologists were also getting tired of being pushed around by the physicists. Perhaps emboldened by the resistance from geologists and some physicists, they too started arguing that the evidence from paleonotology for an old Earth was too strong to be dismissed, and that the cause of any discrepancy with the results from physics lay with physics and not with biology.

The professor of zoology at Oxford Edward Poulton (1856-1963), in a talk to the British Association in 1896, picked up on some recent critiques of Kelvin’s work by other physicists that had pointed out that if one changed Kelvin’s assumptions of the thermal properties of the Earth by relatively small amounts, the age of the Earth could be made to increase by a factor of over fifty. Poulton then made the case as to why the case for an older Earth based on biological and paleontological evidence should not be dismissed. He pointed out that:

[E]volution results first in the divergence of general characteristics and then of specific characteristics, that natural selection requires much longer to alter simple organisms than more complex ones, and that the origin of no phylum can be found anywhere in the stratified record – he proceeded to argue that the degree of specialization found in the lower fossils can only be accounted for by a very long period of evolution prior to the beginning of geological record. (Burchfield, p. 139)

He concluded that the physicists must be wrong about their young Earth.

This was the state of affairs near the dawn of the twentieth century. It was an impasse, with geology and physics at loggerheads, and the theory of evolution by natural selection hanging in the balance, whose fate would be decided by which side would emerge the ultimate winner.

(Main sources for this series of posts are The Chronologers’ Quest: The Search for the Age of the Earth (2006) by Patrick Wyse Jackson and Lord Kelvin and the age of the Earth by Joe D. Burchfield (1975).)

POST SCRIPT: Andrew Schlafly on The Colbert Report

I have written about Andrew Schlafly and his wacky Conservapedia project before (see here and here) but had never seen him before until this interview.

He seems a little weird and creepy to me.

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The age of the Earth-8: Geologists at loggerheads with physicists

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series on the age of the Earth, see here.

While Kelvin’s estimate of the age of the Earth was interesting in its own right and faced its own supporters and detractors, the undeniably important consequence of his work was that for the first time, pinning down an actual age for the Earth became a question that had the potential to be definitively answered, and this spurred the growth of an entire research area. What Kelvin did that was of immense importance were two things: he demolished the uniformitarians’ vague notions of an almost limitless time for the age of the Earth and established the importance of doing precise calculations; and he began the process, and highlighted the importance, of unifying scientific theories in formerly divergent fields, by introducing physics principles into geological studies.

Kelvin had arrived at an age for the Earth that made it very difficult for natural selection to succeed as a mechanism. Then, as now, results from physics tend to be regarded as on a sounder footing than those from other disciplines. Hence those other fields such as geology and paleontology and biology tend to try and conform to the constraints provided by physics, not the other way around. Kelvin’s estimate of 100 million years as the upper limit for the age of the Earth became part of the scientific lore and geologists and biologists scrambled to accommodate it by trying to find ways to modify their calculations to be consistent with this upper bound. They had some success since each of these calculations depended on many parameters whose values could not be determined precisely, and so there was some room for flexibility.

As for evolution by natural selection, this low upper limit for the age of the Earth caused serious problems. As a result of Kelvin’s and other people’s strong criticisms of the idea of an Earth that was hundreds of millions of years old, by the third edition of Origins, Darwin had abandoned his breezy calculation of a 300 million year old timescale for the formation of the Weald, done somewhat casually at a time when such an age seemed reasonable. Meanwhile Wallace published another book in 1880 that suggested that 200 million years was sufficient for evolution to have worked (Jackson, p. 193). By squeezing here and pinching there, it seemed possible (though just barely) to accommodate 100 million years as sufficient for natural selection to work, but only with great difficulty and at the risk of sacrificing plausibility.

By around 1880, an uneasy truce seemed to have been drawn among the physics, geology, and biology communities around a 100 million year old Earth. But it did not last long. Others came along who followed up on Kelvin’s methods and using more refined calculations and newer estimates for the parameters involved, arrived at even shorter ages of 40 million and then 20 million years for the age of the Earth. Most important among these was an 1893 calculation by Clarence King, the first director of the US Geological Survey who, again basically using Kelvin’s thermal methods, arrived at a figure of 24 million years. In a paper in 1897, towards the end of his long and illustrious career, Kelvin stated his conclusion that the Earth was between 20 and 40 million years old, with King’s value of 24 million being likely most correct.

This caused immense problems for the other areas of science. If it was true, then almost all of geology would have to be drastically re-conceptualized and the theory of evolution by natural selection would have to be thrown out the window, to be replaced by some teleological model of directed evolution that implied planning or design or some other form of supernatural intervention.

But geologists had had enough of conforming to the ever-increasing restrictive limits of the physicists and modifying their parameters accordingly. Their discipline had now been around for about a hundred years and the newer generation of younger geologists no longer felt like new kids on the block who could be pushed around so easily by the big physics bullies. They felt that 100 million years was as far as it was reasonable for them to go given their own methods of estimating the ages of geological features based on rates of formation and erosion and sedimentation. They dug in their heels and became more assertive, saying that the laws of geology were firmly enough established to rule out such a young Earth and boldly suggested that it was physics that had gone awry somewhere, even if they could not find fault in its calculations or point out where the problematic assumptions were.

Next: What about biology and natural selection?

(Main sources for this series of posts are The Chronologers’ Quest: The Search for the Age of the Earth (2006) by Patrick Wyse Jackson and Lord Kelvin and the age of the Earth by Joe D. Burchfield (1975).)

POST SCRIPT: If the shoe were on the other foot…

If there is one thing that The Daily Show is particularly good at it is showing how ridiculous something is by reversing roles.

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The age of the Earth-7: The Earth starts getting younger again

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series on the age of the Earth, see here.

Darwin and Wallace published their theory of natural selection at a time when it seemed that they had all the time they needed for their theory of natural selection to work. But that window of freedom of long geological times was soon to close and, starting around 1860, newer estimates of the age of the Earth started to shorten it considerably. Part of the reason was undoubtedly a backlash to the success of Darwin’s theory of evolution that, within a decade of the publication of Origins in 1859, had persuaded almost the entire scientific community that evolution was a fact and that its basic idea that all organisms arose from descent with modifications from common ancestors was true.

Acceptance of evolution did not mean that people had given up on god altogether. Most people, including many in the scientific community, were still religious and sought to find ways to preserve a role for god. While they accepted evolution as a fact, what these people found difficult to stomach was Darwin and Wallace’s mechanism of natural selection as the driving force for the process, because this implied that evolution is directionless. Especially troubling was its implication that humans were an accident, not guaranteed to appear, and thus could not be part of any original design plan that god would have had.

There were competing models that preserved this idea of design and thus had a potential role for god and these were the ones favored by religious scientists. Theistic evolution (in which god guided the process of evolution in unspecified ways), orthogenesis (in which it was postulated that organisms contained within themselves a directional mechanism that resulted in continuous improvement), and Lamarckism (in which the acquired characteristics of an organism were somehow transmitted to its progeny) all had the possibility of a role for god, or at least had some directionality that implied that humans were the inevitable result of a grand plan. Natural selection offered no such consolation.

What religious scientists realized was that the smaller the value arrived at for the age of the Earth, the more unlikely it was that natural selection could be the mechanism for evolution. A younger earth implied the need for some agency to speed up the process of evolution and what could that agency be other than god? (In this respect, they were much like modern day intelligent design creationists.) And so there was a strong motivation to lower the upper limits on the age of the Earth and thus strengthen the case for the alternatives to natural selection.

But it must be emphasized that even this was a far cry from the efforts of present day creationists to resurrect a 6,000 year-old Earth. Even the religious scientists of that earlier time had by then rejected that idea with its supernatural catastrophes as absurd and no serious scientist for the past 200 years has even considered that possibility (Burchfield, p. 37). Anyone who argues for such a young Earth has rejected science altogether. These religious scientists accepted evolution as a fact. What they were hoping for is that their methods of estimating the age of the Earth using purely scientific methods would yield results that were of the order of a hundred million years or less, which would be too tight a timescale for natural selection to work.

It was the physicist William Thomson (1824-1907), better known by his later title of Lord Kelvin, who seriously threatened to overthrow the natural selection mechanism for evolution. Kelvin was opposed to evolution by natural selection because it seemed to rule out design in nature and thus left no role for god (Burchfield, p. 33). Kelvin had already established a reputation as one of the foremost physicists of his day, pioneering important work in the study of thermodynamics, especially with the first law (that dealt with the conservation of energy) and the second law (that dealt with the dissipation of heat energy and the consequent directionality of heat flow). So his words were taken seriously, since physics was seen as the most well-established of scientific disciplines.

What Kelvin did was to apply the laws of physics to three different kinds of calculations for the age of the Earth: calculating the age of the Sun to set an upper limit, examining the role that tidal friction played in shaping the Earth, and treating the Earth as a solid cooling body, all of which gave him similar results, persuading him that he was on the right track (Jackson, p. 200).

In the most important of those methods, the cooling method, what Kelvin did was similar to the idea of Buffon in 1778, except that the laws of physics, especially thermal physics, had advanced considerably since Buffon’s time, and Kelvin himself had played a major role in that advancement. Kelvin assumed that all the Earth’s (and Sun’s) energy originated as gravitational and mechanical energy in the particles and possibly meteors that preceded its formation, and that as they coalesced to form the Earth, this gravitational energy was transformed into heat energy that made the Earth into a hot molten ball. The Earth then gradually cooled and solidified as this heat was slowly radiated away into space.

Knowing the mass of the Earth and the Sun and making various assumptions about the initial kinetic energy of the particles, the state of the Earth’s core, and the rates of conductivity of heat from that core to the surface and radiation into space, in 1862 Kelvin came up with upper limits for the ages of both, captured in his statement that the Sun “has not illuminated the earth for 100,000,000 years, and almost certain that he has not done so for 300,000,000 million years.” He also estimated that the Earth was somewhere between 20 million and 400 million years old, with the likely figure being 98 million (Burchfield, p. 36). In 1868, he revised his calculations and made an even stronger statement, that the Earth was no more than 100 million years old (Burchfield, p. 43). He thus flatly contradicted Darwin’s calculations of 300 million years for the time taken for the denudation of the Weald.

Kelvin had thrown down the gauntlet to the geologists and biologists and the next fifty years would result in a struggle to see which side would emerge the winner: the young Earthers of that time (which meant ages of less than 100 million years, not the ridiculous 6,000 years of the present-day creationist young Earthers) or the old Earthers.

(Main sources for this series of posts are The Chronologers’ Quest: The Search for the Age of the Earth (2006) by Patrick Wyse Jackson and Lord Kelvin and the age of the Earth by Joe D. Burchfield (1975).)

POST SCRIPT: Playing dumb

If there is anything more annoying than people who pretend to be smarter and more knowledgeable than they are, it is people who pretend to be stupider than they are.

What is particularly sad is that Fox News must think their viewers don’t like people who actually know stuff and would prefer the stereotypical dumb blonde.

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The age of the Earth-5: Christianity tries to deal with an old Earth

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series on the age of the Earth, see here.

By the end of the 18th century, Enlightenment values had taken hold, science and rationality were on the rise, and religion could no longer rely on dogmatic assertions and threats alone to suppress ideas that it found unpalatable. So the strategy shifted to creating alternative narratives that had a scientific veneer that would make their religion-based conclusions more acceptable. That strategy has been the one that religions have followed ever since, right down to the present day, with intelligent design being its latest incarnation.

In reaction to the rise in the mid-19th century of uniformitarianism in geology and its concomitant idea of an old Earth, there was a resurgence of Biblical literalism that manifested itself in an alternative school of thought known as Neptunism, that argued that water was the main cause of changes in the Earth’s features. This theory was favored by those of a more religious bent who were seeking ways to reconcile science with the Bible.

Some of the adherents of Neptunism were convinced that the Great Flood of Noah was sufficient to preserve the biblical chronology and this group steadfastly rejected any attempts to make the Earth older than 6,000 years or so. One of the most well known of the proponents of this theory was George McCready Price (1870-1963), who tried to make the case that scientific evidence supported a strictly literal interpretation of the Bible. The numbers of this group remained small until the recent rise of the creationist movement that was facilitated by the publication in 1961 of the book The Genesis Flood by John Whitcomb and Henry M. Morris that built on Price’s ideas. While Whitcomb was a theologian, Morris had a doctoral degree in hydraulic engineering with minors in geology and mathematics. He later founded the Institute for Creation Research in 1970 to advance these ideas.

But most religious scientists in the late 18th and early 19th centuries were willing to concede that a strict biblical chronology was too restrictive and required the existence of unrealistically strong forces to create its effects in such a short time. As is the case, when faced with incontrovertible scientific evidence that what they were asserting all along as divinely inspired was simply wrong, sophisticated religious apologists now came up with new interpretations of scriptures that conveniently seemed to conform with an old Earth. They then, as usual, argued that this agreement shows that the Bible is correct because it predicted the scientific discovery of an old Earth!

One version of this new biblical interpretation is what is known as the ‘Gap’ or ‘Ruin-Reconstruction’ theory that arose in the early 19th century. This theory conveniently found a ‘gap’ between Genesis 1:1 (“In the beginning God created the heavens and the earth”) and Genesis 1:2 (“Now the earth was [a] formless and empty, darkness was over the surface of the deep, and the Spirit of God was hovering over the waters”) that allowed for an indefinite amount of time and the shoe-horning in of a very old, unspecified age of the universe in which matter was first created, followed by non-human life and the formation of fossils.

This gap allowed for multiple cataclysms and creations and is flexible enough to accommodate most geologic evidence. But when it comes to the first appearance of humans, the model becomes that of standard creationism with a Garden of Eden and the first humans Adam and Eve created in six 24-hour days in 4004 BCE followed in 2348 BCE by Noah’s flood, which in this model need not be a global flood but could be a local phenomenon.

A weaker formulation of creationism has an even more flexible structure and is known as the ‘Day-Age’ model. This allows for a very old, unspecified age of the universe in which matter was first created, followed by life, the formation of fossils, and finally human beings. Noah’s flood was a historical event in this model but it could be a local phenomenon. The six ‘days’ of creation in the Genesis story are interpreted metaphorically as representing long but indeterminate periods of time, whence comes the name of this model, and hence all these events have unspecified dates that can accommodate values obtained using the standard dating techniques of science. Adam and Eve and the Garden of Eden story are also interpreted metaphorically and not as actual historical events. (For a history of evolution of creationist thought, see Ronald Numbers, The Creationists: The Evolution of Scientific Creationism, 1992.)

William Jennings Bryan, a key player in the Scopes trial of 1925, seemed to be a believer in the ‘day-age’ model but under questioning in the trial, probably for tactical reasons related to the specifics of that case, responded as if he was a believer in the ‘gap’ model.

Nowadays one rarely finds people who believe in the gap model. Christians seem to be either young-Earth/Flood Geologists or some form of day-agers. Islamic creationists and some sophisticated Christian apologists (such as the intelligent design people) today also seem to adopt the ‘Day-Age’ model, hoping that it will make the science-religion contradictions less obvious.

But enough of religious apologetics and its sad attempts at rescuing faith using religious and historical revisionism. The next post gets back to the scientific history of calculations of the age of the Earth.

(Main sources for this series of posts are The Chronologers’ Quest: The Search for the Age of the Earth (2006) by Patrick Wyse Jackson and Lord Kelvin and the age of the Earth by Joe D. Burchfield (1975).)

POST SCRIPT: Jesus Christ – The Musical

The age of the Earth-4: The strategy of religions in response to scientific advances

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series on the age of the Earth, see here.

The history of the science-religion conflict follows a standard pattern. Religions make claims that lie within the framework of science, saying those claims must be true because of their divine origin (because of revelation or religious texts). Then it fights any scientific advances that challenge those claims. Then when the evidence becomes too great and further opposition becomes ludicrous, they concede the point and retreat to a new line of defense. Then after some time has elapsed to allow people to forget its previous objections, religions argue that the very scientific discoveries that they once vigorously opposed now actually support their religious beliefs. They sometimes even go so far as to suggest that their religion actually predicted them. (The comic strip Jesus and Mo has something to say on this here, here, and here.)

A wonderful example of this is the church’s persecution of Galileo because of his support for the Copernican heliocentric model of the solar system. The Catholic Church only apologized for this in 1992. But it did not stop there. It went further and suggested that Galileo’s research was actually divinely inspired with Pope John Paul II saying, “Galileo sensed in his scientific research the presence of the Creator who, stirring in the depths of his spirit, stimulated him, anticipating and assisting his intuitions (my italics).”

Really? Who knew? Why wasn’t the Creator similarly “stirring in the depths” of the spirit of the Pope in Galileo’s time to let him know that Galileo was on the church’s team and to stop bugging him? And was god so busy with other things that he waited nearly 400 years to correct this misunderstanding that has been one of his church’s greatest embarrassments? Ah, the inscrutable ways of god, who works in mysterious ways that we mere mortals cannot comprehend. What we see as incredible stupidity or laziness is actually part of some deep plan that will be revealed to us when we are ready or die.

With regard to evolution, after over a century of opposition, Pope John Paul II in a speech in 1996 to the Pontifical Academy of Sciences made a grudging concession that Charles Darwin may, just may, have been onto something with his crazy ideas:

[N]ew findings lead us toward the recognition of evolution as more than a hypothesis. In fact it is remarkable that this theory has had progressively greater influence on the spirit of researchers, following a series of discoveries in different scholarly disciplines. The convergence in the results of these independent studies—which was neither planned nor sought—constitutes in itself a significant argument in favor of the theory.

(Note how even the Pope recognizes that it is the interconnectedness of modern science, the “convergence in the results of these independent studies”, that gives its conclusions such strength.)

It took fourteen years for the other shoe to drop on evolution, with the church now actually claiming credit for the basic idea of evolution. Archbishop Gianfranco Ravasi, head of the Pontifical Council for Culture, said just this year that “while the Church had been hostile to Darwin’s theory in the past, the idea of evolution could be traced to St Augustine and St Thomas Aquinas” (my italics).

Isn’t that sweet? They knew about evolution all along but decided to keep it secret for 1,500 years until Darwin spilled the beans, and then fought it for another 150 years, before deciding that it was time to whip off the mask and say that they were the original evolutionists, and that they had just been kidding all along about their opposition to the theory.

The age of the Earth provides another humorous example of the church rewriting history in this way. For example, this Catholic website says that “The Church has always agreed with scientists on matters such as the age of the earth and the authenticity of the fossil record” (my italics) while another Catholic website goes into the usual routine of suggesting that god was inspiring these scientific discoveries all along: “The question about the origins of the world and of man has been the object of many scientific studies which have splendidly enriched our knowledge of the age and dimensions of the cosmos, the development of life-forms and the appearance of man. These discoveries invite us to even greater admiration for the greatness of the Creator, prompting us to give him thanks for all his works and for the understanding and wisdom he gives to scholars and researchers” (my italics).

But of course these ingenuous statements that the church “has always agreed with scientists on matters such as the age of the earth” and been thankful for the “understanding and wisdom he gives to scholars and researchers” is flatly contradicted by the historical record. Buffon’s 1778 calculation that the Earth was 75,000 years old considerably upset the religious people of his day and the theologians at the powerful Sorbonne created a huge fuss and demanded that he publish an apology for publishing results that contradicted the biblical chronology. Buffon made some apologetic remarks in later editions of his book but did not withdraw the book or repudiate his conclusions (Jackson, p. 111).

Fortunately for Buffon, by his time freethinking was on the rise, people like Baron D’Holbach were publishing atheist treatises blasting the church and religion, and the church had lost the kinds of punitive powers that it had during the periods of the Inquisition so the church could do nothing more to Buffon than castigate him and he was tough enough to withstand their pressure.

As a result of Buffon’s work the genie was now out of the bottle and from then on scientists looked elsewhere than the Bible to answer questions about the age of the Earth. The rise of catastrophism and its concomitant idea of a very old, perhaps infinitely old, Earth came to dominate thinking by around 1850.

Once an old Earth became such an established fact that further opposition to the idea became just silly, how did Christianity respond? That will be discussed in the next posting.

(Main sources for this series of posts are The Chronologers’ Quest: The Search for the Age of the Earth (2006) by Patrick Wyse Jackson and Lord Kelvin and the age of the Earth by Joe D. Burchfield (1975).)

POST SCRIPT: What if life is found on other planets?

Stephen Colbert explores the implications for Christianity.

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The age of the Earth-3: The Earth gets old again

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series on the age of the Earth, see here.

The Enlightenment brought with it the separation of scholarly thinking from religious dogma and this enabled scientists to think much more freely and broadly about all matters, including the age of the Earth.

As the desire for conformity with biblical estimates weakened, scientists started devising theories of the formation of the Earth and the universe and doing calculations that were not explicitly linked to Biblical theories. Immanuel Kant (1724-1793) and Pierre Laplace (1749-1847) created a new model of the universe, the nebular hypothesis, that said that stars and planets originated as clouds of gases. They used Newton’s laws of mechanics and his theory of gravitational attraction to explain the formation and evolution of the solar system.

Comte de Buffon (1707-1788) was one of the first to try and determine the age of the Earth using only scientific theories and data. He used estimates of the initial internal heat of the Earth and its rate of cooling to arrive at a value of about 75,000 years, a result that he published in 1778 (Jackson, p. 117). Although the number seems laughably low now, we must remember that he was working before the age of modern thermodynamics and at a time when the Fahrenheit temperature scale and thermometers were just coming into being. Buffon had to estimate the parameters involved in cooling by making judgments of when two objects were the same temperature by the crude methods of actually touching them with his hands.

Buffon’s result, though wildly off the mark by modern standards, was a significant development in two ways. First because it used purely scientific theories to arrive at an age and second because the age he reported broke with a Bible-based chronology completely, going well over the 6,000 years that people believed the Bible required.

This development stimulated the field of geology and paleontology as scientists interested in those fields now started to investigate the origins of the Earth and its fossils without the artificial constraints of the biblical chronology. People like Nicolaus Steno (1638-1687) and Robert Hooke (1635-1703) had earlier observed the presence of sea-shells and other fossils on mountain tops, and the patterns in the layers of rock strata, and had used that information to create theories of geological formation, in which rock layers were formed slowly by sedimentation and newer layers of rock lay on top of older ones. But they had not used them to actually try and date the Earth, because the biblical ages were the standard beliefs in their time.

But now their early work became the basis of the new geology, by combining the theory of slowly sedimental formation with the ordering of fossils in the layers of rocks in which they were found. The clear pattern of evolution that emerged of the appearance of fossils in the rock strata (with simpler fossils being found in the older layers lower down and more complex ones in younger layers higher up) led to later paleontologists such as Georges Cuvier (1769-1832) and Jean-Baptiste Lamarck (1744-1829) suggesting that the process of geological formation must have been quite slow, and required far more time than the Genesis story allowed. A few paleontologists even went back to the old idea that the Earth had existed forever. Even though these paleontologists were Christians (Steno, for example, was a priest and Cuvier was religiously orthodox), they all felt that the Bible should not be the source of data for investigating the age of the Earth and that only the evidence of the Earth itself could reveal its origins.

A major development occurred when James Hutton (1726-1797) published a paper in 1785 that argued that catastrophes and great floods were not necessary to explain the features of the Earth; that they could have been caused entirely by the slow and steady accumulation of small changes. In 1788 he argued in a paper that not only was the Earth infinitely old, it would also last forever saying, “The result, therefore, of our present enquiry is that we find no vestige of a beginning – no prospect of an end.” (Jackson, p. 92).

This marked the birth of the idea of uniformitarianism and it was clear to this school of thinkers that adopting this meant that the Earth had existed for a vast amount of time. Some thought it extended back infinitely far while others thought it was extremely old, so old that they were not that interested in pinning down an actual age or thought that it could even be done. They assumed that sufficient time was available as needed for their model of slow rate of changes to produce the desired large effects.

Meanwhile, what was the response of Christians to these grave challenges to their biblical chronology? That will be examined in the next post.

(Main sources for this series of posts are The Chronologers’ Quest: The Search for the Age of the Earth (2006) by Patrick Wyse Jackson and Lord Kelvin and the age of the Earth by Joe D. Burchfield (1975).)

POST SCRIPT: Mr. Deity gets a tour of hell from Lucifer (Lucy)

The Jesus people should add this to their spiel, since they are obsessed with the idea of other people going to hell.

The age of the Earth-2: The Earth gets its first birth day

(My latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom has just been released and is now available through the usual outlets. You can order it from Amazon, Barnes and Noble, the publishers Rowman & Littlefield, and also through your local bookstores. For more on the book, see here. You can also listen to the podcast of the interview on WCPN 90.3 about the book.)

For previous posts in this series, see here.

For a long time, people were comfortable with the idea that the Earth and the universe might have been in existence for an infinite time and is undergoing repeated cycles of creation and destruction.

Things changed with the arrival of Christianity. That particular religion could not tolerate the idea of the universe occurring in cycles because that would mean that Jesus was dying over and over again for our sins, which seemed preposterous. (The discovery of sentient life on other planets is going to create problems for fundamentalist Christians as it is not clear how they would fit into the whole ‘original sin and Jesus sacrifice’ model.) So there had to be a chronology with a definite beginning and this acted as a spur to make calculations to fix the date of creation. Theophilus of Antioch (~115-183 CE), a convert to Christianity, provided an early estimate that the Earth had existed for 5,698 years until his time (Jackson, p. 13) and Julius Africanus (~200 CE) gave the creation date as 5500 BCE (Burchfield, p. 4).

These Christians based their calculations using an interpretation of the Bible (found in Psalms 90:4 and 2 Peter 3:8) that held that the Genesis story of six ‘days’ of creation was a metaphor, where each ‘day’ represented 1,000 years. The total of six days of creation was interpreted as meaning that the universe would last a total of 6,000 years. The appearance of man on the sixth day of the Genesis story represented the arrival of Jesus sometime in the last 1000 years. These calculations, based as they were on metaphorical readings of the text, lacked a certain rigor.

It took until the 1600s for the age of the Earth to become really quantified, with scholars getting down to the nitty-gritty of calculating an actual age, with the Bible again being the main source of data, and the results obtained strongly influenced thinking in the Western world. I have written before of Bishop Ussher’s (1580-1656) calculation of October 22, 4004 BCE as the day of creation (see part 1 and part 2 ) but his was just one, and not even the first, of many precise calculations around that time that used various versions of the Bible and thus arrived at slightly different values that rarely differed by more than a thousand years.

Why there was such an explosion of so many calculations done in the early 1600s is a bit of a mystery. One suggestion is that people began to realize that if the Earth was only going to last exactly 6,000 years total, then the end of the world was quite near and hence calculating the exact age of the Earth was of practical importance. After all, if you knew for sure that the world would end in a specified year with the return of Jesus, then you could make appropriate plans, or so at least religious people think though I am at a loss as to what one might do. One finds the same kind of obsession amongst present day Rapturists. They work feverishly to look for signs of the end times because they think it is very near. People seem to be strangely drawn to the idea of an imminent apocalypse, as can be seen in the commercial success of films based on that theme.

The first Bible that had carried a chronological marginal creation date was published in 1679 but it was the insertion of the creation date of 4004 BCE and the dates of other significant biblical events next to the relevant sections of Genesis in the annotated versions of the authoritative King James Bibles in 1701 that cemented that date in the public consciousness. These marginal dates continued to be printed until the late 20th century. Ussher was not cited as the source of the dates and may not even have been the source since there were other chronologies, such as that of William Lloyd (1627-1717) who became the Bishop of Worcester in 1699, that also arrived at the date of creation as 4004 BCE. Since the latter was considered the foremost chronologer of his time, he may well have been the source of the date with which Ussher is now indelibly linked, although it is also possible that his calculations were strongly influenced by Ussher’s earlier work (Jackson, p. 30).

Whatever the original source of the date, the blame for leading present day fundamentalist Christians into an anti-science cul-de-sac from which they have never emerged surely must lie at the feet of John Fell (1625-1686), Bishop of Oxford and Dean of Christ Church College and the person who for some time controlled the operations of the Oxford University Press. It was he who in 1672 proposed putting the creation date in the King James Bible. If not for that, it is possible that the idea of a 6,000 year-old Earth may have remained a speculation, one among many, that could be interpreted away as science advanced, as has happened to so many other beliefs. But putting it in the hugely influential King James Bible raised it to the level of an infallible truth for many Christians because of their belief that if something is in the Bible, it must be literally true.

Western scientists at that time (or natural philosophers as they were then known) were mostly Christians and while they may not have been as convinced about the ideas of end of the world and Jesus coming again, they saw no reason to challenge the Bible-based calculations as to the date of creation. They took their cue from these biblical calculations and saw their purpose as trying to explain how life could have appeared and how geological forces could produce the features of the Earth, such as mountains and ravines, within that short time. This naturally led to biological theories of special creation and geological theories of catastrophism, a model in which sudden and violent upheavals produced major geological changes.

While some Christians then (and young Earth creationists now) may have seen Noah’s flood as the single major catastrophe that produced all the main features, other less Biblically-literal minded scientists such as Rene Descartes (1596-1650) and Gottfried Wilhelm Leibniz (1646-1716) were willing to consider multiple catastrophes, with fire and water as the agents of these major changes, while still sticking with the biblical chronology (Burchfield, p. 5).

But with the Enlightenment, the desire for conformity with biblical estimates weakened, and people started devising theories of the formation of the Earth and the universe and doing calculations that were not explicitly linked to Biblical stories. These developments will be examined in the next post in the series.

(Main sources for this series of posts are The Chronologers’ Quest: The Search for the Age of the Earth (2006) by Patrick Wyse Jackson and Lord Kelvin and the age of the Earth by Joe D. Burchfield (1975).)

POST SCRIPT: Book signing and reception

Tomorrow (Thursday, December 3, 2009) there will be a short talk by me on my latest book God vs. Darwin: The War Between Evolution and Creationism in the Classroom, followed by a book signing and reception. All are welcome.

Where: Flora Stone Mather room at the Kelvin Smith Library, Case Western Reserve University
Time: 3:00-4:00 pm