(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.
[Read more…]

(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.
[Read more…]

(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.
[Read more…]

(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.
[Read more…]

(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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(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.
[Read more…]

(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.
[Read more…]

(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.)
[Read more…]

(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.
[Read more…]

(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