Centuries before Modern Geology

Aristotle thought the universe had existed eternally. Roman poet Lucretius, believed that the formation of Earth must have been relatively recent, given that there were no records going back beyond the Trojan War. The Genesis account of creation would, if taken at face value imply a young Earth, only 6,000 years old. This is a result of narrow literalism that Judeo- Christian scholarship adhered to with some exceptions. Like Maimonides, in the 12th century sought compromise with Aristotle’s infinitely old earth idea by suggesting that the days of Genesis reflected indefinitely long periods of time. But this does not qualify as a scientific argument, since Maimonides invoked no observational evidence. Neither did Aristotle.

Today, young Earth creationists seem like vestiges left behind from that pre-modern age. The Islamic tradition was unique in this sense that while the Aristotelian infinitely old earth theory had serious critics but that didn't make them supporters of the Young Earth idea. It could be attributed to the language and the style of the Quran that it doesn't allow for a literalist reading of the ‘Days of Creation’ as a ‘day’ in the Quran can be as long as one to fifty thousand years long. So Muslim thinkers relieved from undue literalism with regards to time found themselves free to directly ask mother earth her age.

How do we know the age of the Earth?

The process of scientifically estimating the age of the Earth revolves around, essentially, finding the oldest piece of the planet we can, then figuring out how old that piece is. Finding super old rocks is conceptually straightforward, but practically difficult or near to impossible. Because of plate tectonics, Earth is constantly recycling its different layers, breaking them down into magma in the interior before pumping it back up to the surface once more. But old rocks do exist, and the oldest rock we know is a tiny piece of zircon found in western Australia. The process of figuring out a rock's age often falls to the scientific techniques of radiometric dating and Uranium-lead conversion technique.

Now let’s talk about how we got so far. The following two sections are related. The first will present the European scientists who are attributed with major shifts in the history of Earth Sciences. And the next will discuss two Muslim polymaths who anticipated these ideas centuries before their European counterparts.

A comparative analysis will be required of the reader to understand what many scholars have pointed out of the discrepancies of our reading of the history of science, where Muslim contributions are either intentionally undermined and ignored or conveniently attributed to Greek sciences.

European scientists and the discovery of an ancient earth

Every story of science always starts in Europe or catapults itself from Greek Antiquity to the European Renaissance. The general attitude of Western academia until recently has been of turning a blind eye to the millennia in between, that saw the flowering of a rich scientific tradition in the Muslim world. So in this light, the historical scheme presented is as follows:

1. Pre-European literature (Aristotle and his circle of influence. This is where Muslim achievements are typically squeezed in).

2. The Formative stage between 14th to 17th centuries (Western Earth Sciences).

3. The development of geologic theories between the 18th and 19th centuries.

Let's start with Aristotle, who hypothesized the eternality of the universe which included an infinitely old earth. This reasoning had more to do with philosophical speculation and metaphysics. Earth Sciences are essentially defined by field observations and scientific data. This latter feature was codified in the Islamic Scientific tradition especially in the works of two great polymaths. Ibn Sina and Al Biruni are on the two sides of the Aristotelian spectrum. While Ibn Sina was a supporter of Aristotelian thought and he appropriated it to the Islamic worldview. Al Biruni was a critic. But the important observation (as we shall see) is that both display a very modern scientific spirit in their geological inquiry and appeal to natural and historical causes when discussing the antiquity of the earth. This is in sharp contrast with Aristotle’s method.

Leonardo Da Vinci (1452-1519) is a significant figure in the formative period. Mears writes, “Da Vinci’s notebook shows that he clearly appreciated the nature of fossils, of erosion, transport and deposition, and of shifting of seas and land. Free from dogmatic misconceptions, he was a naturalist far ahead of his time. Unfortunately, his geologic ideals were lost for several centuries” [1]

Why was it lost? Due to something that distinguishes attitudes towards science in Europe from medieval Muslims who preceded them by centuries. (Discussed in the last section).

In the 1660s Nicolas Steno formulated modern concepts of deposition of horizontal strata. His work gave way to what was called the Law of superposition of strata. [2] This was originally Ibn Sina’s theory as we shall see.

A century later, William Smith realized that rock layers at distant locations came from the same time period. He created a catalogue of strata and argued that each one represented a distinct time in Earth's history — a principle known as fossil succession. This again is one of Ibn Sina’s great contributions to the study of fossils. [3] The accumulating evidence pointed to an extraordinary new idea: that the history of Earth goes back much, much further than any human memory. In 1788, Scottish geologist James Hutton published his Theory of Earth, which introduced the world to the idea of “deep time.” The implications of the treatise were revolutionary: Not only was the Earth not young, but it was not static, Hutton said. The same geological forces that operate today, like deposition, erosion and uplift, have been shaping the Earth for ages. Hutton’s theory of the Earth had essentially called for the recognition of the fact that earth processes are continuous on Earth. This led to the doctrine of uniformitarianism or the concept that the earth‘s surface was shaped by erosion, and by small sudden changes, such as earthquakes, rather than by sudden catastrophic acts. [4]

Recent studies by the historian, Porter on the history of Earth Science in Britain raised some points on the nature of Hutton’s theory of the Earth as being alien to the traditional school of thinking in Britain. It was known that he spent some time studying Medicine and Law in Leiden and Paris both of which housed large volumes of Islamic manuscripts before the 15th century. [5]

Now let’s highlight some of the intellectual achievements of two of the most eminent scholars of the Islamic Golden Age, al-Biruni and Ibn Sina, both of whom correctly inferred the antiquity of the Earth from scientific observations and geological arguments.

Al Biruni- The man who ‘scientifically’ discovered America.

Using a combination of carefully controlled observation, meticulously assembled quantitative data, and rigorous logic, Al Biruni deduced that there has to be landmass on the other side of the globe. He mused, would the forces and processes that had given rise to land on two-fifths of Earth’s belt not also have made themselves felt in the other three-fifths as well? Reasoning thus, Biruni concluded that somewhere in the vast expanses of ocean between Europe and Asia there must be one or more unknown landmasses or continents.

What’s interesting about Al-Biruni is that he was not an Aristotelian; indeed he had a very long correspondence with Ibn Sina in which he pointed out that much of what the Aristotelians regarded as proof was in fact mere speculation.

Free from the need to fit what he saw into a pre-existing theoretical framework, he wrote in his great work on India of what he saw.

“If you have seen the soil of India with your own eyes and meditate on its nature – if you consider the rounded stones found in the Earth however deeply you dig, stones that are huge near the mountains and where the rivers have a violent current – if you consider all this, you could scarcely help thinking that India has once been a sea which by degrees has been filled up by the alluvium of the streams.” [6]

Both of his insights; Land being covered with water and the processes of deposition must have taken considerable time, were the main concepts developed in the formative period of Earth Sciences in Europe by Steno, Smith and Hutton.

Ibn Sina- The Polymathic Genius

Ibn Sina was the most popular Muslim thinker in late medieval Europe. The material related to his research on geology was translated into Latin as early as around the 13th century by Alfred of Sareshel, who erroneously attributed it to Aristotle himself. [7] Imagine if Einstein’s General Relativity paper was attributed to Mach or Aristotle’s Nicomachean Ethics to Plato.

As Adams put it; “Avicenna’s views concerning the origin of mountains, have a remarkably modern tone.” [8]

He postulated the theory of the ancient earth in principally three ways. One through an examination of rocks (in line with modern geology), second through proposing that most landmass was submerged under water and third through fossils. All three share a remarkable modern empirical style of enquiry.

He recognized that the formation of rocks in bulk and then mountains and cliffs is a slow process.

“The formation of stones in abundance is either at once due to intense heat (probably referring to arid climate) over vast mud areas; or little by little through a sequence of days. …most probably from agglutinative clay which slowly dried and petrified during ages of which we have no record.” [9]

Avicenna went on to describe the process of the formation of mountains (or heights), after the formation of stones and rock sequences. He suggests that the mountains have been raised up by earthquakes. In this he was anticipating modern ideas of plate tectonics that raises mountain ranges.

“The formation of heights is brought about by (a) an essential cause and (b) an accidental cause. The essential cause (is concerned) when, as in many violent earthquakes. In the case of the accidental cause, certain parts of the ground become hollowed out while others do not, by the erosive action of winds and floods which carry away one part of the earth but not another. “

In analyzing the origin of mountains, Ibn Sina outlines the fundamental principle of superposition of strata, which later in the history of Geology became the Law of Superposition of Strata by Nicolaus Steno in the 17th century.

Historians of Geology, Toulmin and Goodfield write "Around 1000 AD, Avicenna was already suggesting a hypothesis about the origin of mountain ranges, which in the Christian world, would still have been considered quite radical eight hundred years later”. [10]

Were large parts of the Earth submerged under water ?

Ibn Sina discussed how the earth is ancient and much of its parts lay submerged underwater for ages. Even Aristotle speculated along these lines. The idea that what is now land was formerly beneath the sea was already present in Aristotle. But Aristotle regarded this as a consequence of the antiquity of the Earth, whereas Ibn Sina, using a more modern style of reasoning, is reversing the argument; the evidence shows that what is now land was once beneath the sea, and this is evidence that the Earth is, indeed, old.

So the Greek approach was theory driven by and large : Propose a theory and then justify it. Whereas the Muslim approach was observation driven: Observe phenomena and then explain it.

Ibn Sina writes, “In many [terrestrial] stones, when they are broken, are found parts of aquatic animals, such as shells, etc.”

Leonardo da Vinci was to come to the same conclusion centuries later, in Renaissance Europe, but while Ibn Sina published his results freely, Leonardo thought it prudent to keep it to himself, and his work on this did not come to light until the 19th century. Why so? Because these opinions would be at odds with the Christian views on the world. And going against the Church was not a wise thing to do in Medieval Europe. 

Summary

 In conclusion, Ibn Sina and Al Biruni presented fundamental principles of geology in terms of the earth’s processes, major events and long geological time. These principles were later known during the Renaissance in Europe as the law of superposition of strata, the concept of catastrophism, and the doctrine of uniformitarianism.

Today the idea of the ancient earth is a necessary conclusion of modern cosmology and astrophysics and a starting point for research in modern geology, archeology even biology, zoology and so on. Remember that the ‘ancient earth’ is a first principle for any evolutionary understanding of life. Did it facilitate Al Biruni’s biological ideas and evolutionary principles? Possibly.

Ibn Sina and Al-Biruni in their different ways correctly inferred the antiquity of the Earth. But the important takeaway from all of this is that they proposed ideas that were rigorously scientific and built on field observations, which in many ways was a break from the Greek approach on the subject and paved the way for modern Earth Sciences

References

[1] Mears, B. Jr., 1978. Essentials of Geology. D. Van Nostrand Co., New York.
[2] Steno, N., 1669. An Early Statement of Ordering Principles in Earth History. University of Michigan, Humanistic Studies, Vol. XI, part 2, p. 229-230.
[3] Montasir, A. H., et al, (Editors), 1965. “Al-Shifa” of Ibn Sina. Natural Sciences, Part 5 on Minerals and
Meteorology. Amiri Publication, Cairo, Egypt. 94 p. (In Arabic with summary in French).
[4] Mears, B. Jr., 1978. Essentials of Geology. D. Van Nostrand Co., New York.
[5] Potter, R., 1977. The Making of Geology. Earth Science in Britain 1660-1815. Cambridge University
Press, Cambridge. 288 p.
[6] Alberuni’s India, tr. and ed. E. C. Sachau, Kegal Paul, London, 1910
[7] E. J. Holmyard and D. C. Mandeville, Avicennae De Congelatione et Conglutinatione Lapidum, Geuthner, Paris, 1927, Introduction
[8] Adams, F. D., 1938. The birth and development of geological sciences. First published by Williams & Wilkins Co., Baltimore. 506 P.
[9] Montasir, A. H., et al, (Editors), 1965. “Al-Shifa” of Ibn Sina. Natural Sciences, Part 5 on Minerals and
Meteorology. Amiri Publication, Cairo, Egypt. 94 p. (In Arabic with summary in French).
[10] Toulmin, S. and Goodfield, 1965. The Ancestry of Science: The Discovery of Time. Hutchinson & Co. (Publishers) Ltd., London.