Episode 026 - The Rejection of Young Earth Creationism in the 19th Century

- Decay and refutation of the Genesis minimalist paradigm for interpreting geology.
    - What do contemporary young Earth creationists think happened during this epoch of human history (c. 1700-1830)?
    - Do they think about it at all?
    - Do they think that it was a conspiracy or open rebellion, a force of will to reject the Bible?

- Late 18th / early 19th century debate over the age of the Earth
    - Change in status of fossils of extinct species from a doubted claim to a means of dating strata
        - In Steno's time, the fact that shells of many extinct species clearly do not belong to living animals was considered a telling argument in favor of their abiotic origin.
        - By the early 19th century, enough work had been done on systematic stratigraphy across Europe that geologists recognized a number of extinct fossil groupings that could be found in a variety of places, and the conviction grew that these assemblages were the remains of living communities that existed at specific intervals in Earth's past.
        - In turn, using fossil assemblages to cross-correlate rocks across Europe and eventually across the rest of the planet allowed the erection and refinement of the geological timescale that we still use today.
    - Hutton: "we can see no vestige of a beginning, no prospect of an end"
        - Criticized as bringing back Aristotelian eternalism, but Hutton defends his statement as a comment on the limitations of what we can observe
- Final burst of "diluvialist" theory in the 1820s
    - "Drift", including "erratic" boulders, gravels, and sands in places contemporary streams and gravity could not have left them (e.g. on hillsides)
    - Some such deposits of gravel and sand in Europe and a few other places scattered across the world, particularly in caves, held recent fossils; these were bundled up together and held to be products of either Noah's Flood or a similar flood at a different, somewhat earlier date.
    - No human remains found in these deposits (at the time the debate was being resolved, at any rate).
- Lyell begins publishing "Principles of Geology" in 1830
    - Pushes the Huttonian theme of uniformitarianism to its extreme.
    - Lumps Genesis minimalists, diluvialists, catastrophists, and even directionalists together
    - Lyell's uniformitarianism was never accepted in absolute completeness
        - Even before the advent of thermodynamics in the 19th century, it was still common sense that the Earth is cooling down with time.
- What happened to the evidence once taken as proof of diluvialism?
    - The gradual, halting acceptance of ice ages as the source of "drift"
- Where did the debate go from there?
    - Direct reference to Genesis as a historical reference for geological events died out of the living stream of geological debate.
    - Physicists, and devotees of the new discipline of geophysics, began to look for ways to constrain the Earth's age with the means available to late 19th century physics. The name of William Thomson, later Lord Kelvin, is most remembered today for essentially issuing ultimata to stratigraphers and paleontologists based on his cooling histories of the Sun and the Earth. A tug of war ensued between geologists in these old subdisciplines, whose estimates of the required time for the deposition, uplift, and erosion of strata ran into the hundreds of millions of years, and the physicists, who thought that 100 million years was roughly the longest conceivable time allowable.
    - Of course, the physicists were wrong; their estimates of the age of the Earth were yet another area where the advent of 20th century physics (radioactivity, which ultimately is a quantum physics effect) overturned previous thought:
        - First, radioactivity heats the interior of the Earth--and nuclear fusion drives the Sun--meaning that the old estimates of cooling lifetimes were meaningless.
        - Second, radioactivity gives us many ways of actually calculating numeric ages of minerals and rocks.
        
-The upshot for the debate between young Earth creationists and geologists.
    - It pays to keep in mind that the radiometric dating line of evidence for the long age of the Earth came very, very late in the history of geology. It's not a primary argument, certainly not historically, and perhaps not even scientifically, for an age of the Earth that radically transcends 6,000 years.
    - Geology, like physics, chemistry, and biology, was born in the 17th century, in an intellectual climate steeped in Biblical minimalism. There was no shortage of geologists who *wanted* a global Genesis flood to have existed and left evidence of its passing. They were argued, or even argued themselves out of this belief, very reluctantly.
    - It's also worth taking some time to think:
        - Does the text of Genesis demand a global flood? Really? We are that sure of the definitions of the words and the history of the text?
        - Is a God that presided over the ad hoc instantaneous creation of a complex planet any greater in concept than the God that created a whole universe and the laws that govern its growth and change over 13 billion years?