|Author||Stephen Jay Gould|
|Subject||History of geology|
|Publisher||Harvard University Press|
|Media type||Print (Hardcover and Paperback)|
|LC Class||QE508 .G68 1987|
Time's Arrow, Time's Cycle: Myth and Metaphor in the Discovery of Geological Time is a 1987 history of geology by the paleontologist Stephen Jay Gould, in which the author offers a historical account of the conceptualization of Deep Time and uniformitarianism using the works of the English theologian Thomas Burnet, and the Scottish geologists James Hutton and Charles Lyell.
Gould ranks the development of the concept "deep time," which involved deliberately rejecting the biblical description of earth's past for nearly incomprehensible eons, with the revolutions associated with Copernicus and Charles Darwin. To illustrate this, Gould picked three major figures in the history of geology, one traditional villain (Thomas Burnet) and two traditional heroes (James Hutton and Charles Lyell).
Standard textbook accounts of the achievements of these three figures have long provided what Gould describes as a "self-serving mythology." These flimsy "cardboard" accounts vaunt the superiority of empiricism and inductivism over the scientific nemesis of religious bigotry.
This legend as perpetuated by geology textbooks over the last century claims that geology remained in the service of the Mosaic story of creation so long as armchair geological theorists refused to place fieldwork ahead of scriptural authority. Thomas Burnet was just such an archetypical religious spokesman. A century later, Hutton heroically broke with this biblical zealotry by arguing that geological evidence must rest upon a solid empirical foundation. The Earth's strata, when carefully examined, betray "no vestige of a beginning—no prospect of an end." But Hutton was far ahead of his time. So it was not until Charles Lyell published the Principles of Geology that geologists finally came to accept Hutton's basic message and banished miraculous intervention, catastrophes, and biblical deluges from their science.
Having elaborated this bit of scientific melodrama, Gould proceeds to demolish it by showing that the actualities of Hutton's and Lyell's work were the opposite of the textbook legend. His intention is not simply to debunk the textbook legend, which has already been debunked by historians such as Martin J. S. Rudwick. He sets out to rectify the error and show the real sources of inspiration in the development of deep time which have not been properly understood.
Gould is deeply influenced by Thomas Kuhn's The Structure of Scientific Revolutions (1962). Kuhn argued, in part, that science is a social activity and that theories are intellectual constructions imposed on data, not demanded by them. Along with Kuhn and other philosophers and sociologists of science, Gould has recognized that mental constructs (metaphors, analogies, personal philosophies, imaginative leaps)—not empirical discoveries—are what bring about scientific advance. "Facts" are so embedded in a paradigm that they simply do not have the kind of independent probative power they were once thought to possess.
The development of the idea of deep time is by no means fieldwork, as the textbook myths would have us believe. Rather, Gould pinpoints a powerful pair of metaphors—time's arrow and time's cycle—by which humankind has always tried to grasp the concept of time. Time's arrow captures the uniqueness and distinctive character of sequential events, whereas time's cycle provides these events with another kind of meaning by evoking lawfulness and predictability.
More importantly, this metaphorical pair of ideas was essential to the thinking of the three geological protagonists; and the paired concepts therefore offer the key, now obscured by textbook mythology, to unlocking their thinking about time.
Burnet's theory is a one-cycle theory in which biblical narrative (time's arrow) runs its course within a wider conception of "the great year" and "great circle of time and fate" that bring about the return of Paradise.
It is his belief in Scripture that made Burnet a pariah in the history of geology. Yet Burnet was hardly the religious fanatic he is painted to have been within the context of his contemporary scientific thought.
In contrast to textbook legend, Burnet was adamant about explaining the Biblical history of the earth entirely within the frame of natural science, devoid of all appeals to miracles or divine intervention. Thus this "bad guy" of geological textbook history was actually more devoted to rational, miracle-free science than the greatest scientists of his age.
Before James Hutton, most geological theorists had dealt only with processes of decay. The earth was created and its geologic structures just wore down through catastrophic events like weathering and especially the biblical Flood.
Hutton introduced the concept of repair into geology and, with it, the notion of deep time. The textbook myths see this as a triumph of science and empiricism over religion, but it was nothing of the kind.
Hutton's theory of the earth as a geological clockwork of eroding continents balanced against uplifting ocean basins was not based on field observations but on a priori conceptions inspired jointly by religious considerations and "the most rigid and uncompromising version of time's cycle ever developed by a geologist."
Hutton's theory grew out of what may be called "the paradox of the soil." Good soil, the product of the "denudation," or eroding, of rock strata, eventually loses its richness to the plant life it sustains. Were there no geological source for continual new soil then the world would bear the intolerable stamp of an imperfectly designed abode for man's existence. Hutton's homocentric and teleological concept of the world therefore demanded that the soil, new soil, should never run out. This requirement in turn demanded the uplift of new strata to become the sources for soil replenishment.
So Hutton set out to find evidence for uplift (which he naturally did, since he was looking for it). He found much evidence interpreted to be repeated uplifts of the Earth's crust. This led him inexorably to the idea of deep time.
So rigid was Hutton's vision of an endlessly cycling earth having "no vestige of a beginning" and "no prospect of an end" that he lost all interest in the historical nature of geological change. The Divine benevolence entailed in these cycles was everything to Hutton. Such is an unlikely hero for empiricist geology, who nevertheless became one.
Gould reconstructs the process of mythification of Hutton and sees it as involving several stages.
First, Hutton's long and turgid Theory of the Earth (1795) was popularized by his friend John Playfair (1802). Not only did Playfair make up for Hutton's difficult prose, but he also modernized Hutton's theory by soft-pedaling both his "denial of biblical history" and his repeated appeals to final causes. Subsequently, Charles Lyell, who needed an empiricist hero for his own account of the warfare between science and religious bigotry, bolstered Hutton's image as a fieldworker who had no conceptual bias. Finally the legend was consolidated in the writings of later geologists, who rarely bothered to read Hutton in the original.
It is important to bear in mind that Charles Lyell was trained as a lawyer. His rhetorical skills were considerable and they are crucial to understanding his impact upon the history of geology.
When pleading for his favorite client, which became known as the "uniformitarian" theory of geology, he portrayed the previous history of his discipline as a gradual overcoming of primitive superstitions, wild speculations, and biblical allegiances. In doing so he created his own legend as an arch-empiricist free of all bias and preconception.
But Lyell was not selling just evidence and fieldwork over previous dogma and speculative theory. Rather he foisted upon his contemporaries a "fascinating and particular theory rooted in…time's cycle" by conflating a number of distinct elements under the single banner of "uniformitarianism," the regularity of physical laws with the irregularity of history.
First, Lyell argued for the uniformity of nature's laws (that is, the notion that laws do not change with time or place). Second, he argued for the uniformity of process, which simply means always explaining past changes by currently known causes even if catastrophic interpretations may be just as explanatory. Contrary to legend, Lyell's catastrophic opponents accepted both of these philosophical aspects of "uniformity."
What Lyell's critics did not accept were two further substantive hypotheses about the world that he included under the heading of good (uniformitarian) science.
These claims were that rates of geological change are always uniform and gradual and that the general state of the world also remains uniform (that is, there is no progression or directionality in the long run). Far from using Hutton's field data to show that the earth has passed through vast epochs of change, Lyell drew on the peculiarly static spirit of Hutton's vision to conceive an earth that, although unimaginably old, had changed hardly at all.
The last of these claims was the most peculiar of all within Lyell's vision of earth history. It led him to deny all evidence of progression in the fossil record and hence to reject not only Lamarck's theory of evolution but also contemporary catastrophist notions, in which "higher" organisms were thought to replace "lower" ones after mass extinctions. If fossils seemed to belie this, if mammals were absent from older rocks, it was simply because fossils were rare and scattered.
In showing how Hutton and Lyell were dedicated not to modern notions of geological dynamism but to antique ones of geological steady-state, Gould points out that Lyell was even less of an empiricist than most of his catastrophist and creationist opponents.
For Lyell was constantly forced to deny the literal evidence of the geological record, which shows whole groups of organisms being abruptly replaced by different sets of organisms in adjacent strata. His gradualist reading of the geological record therefore required his constant "interpretation" of the recalcitrant evidence in order to reconcile it with his notions of time's stately cycle and a world without abrupt changes.
Nor was Lyell's eventual conversion to evolution a strictly empirical affair. When he finally took this step publicly, in 1868, it was not because he had been persuaded by Darwin's theory of natural selection. In fact, Lyell rejected that theory, accepting only a general evolutionary process without its celebrated Darwinian mechanism.
Admitting nonmiraculous progression (that is, evolution) in turn allowed him to preserve three of his four uniformities (uniformity of law, process, and rate) while giving up only uniformity of state. This was as Gould notes, "the most conservative intellectual option available to him."
Charles Lyell may have lost the battle over progressionism to Darwinism, but through rhetoric he won a battle against catastrophism, which enabled his hypothesis of the uniformity of rate to become a textbook shibboleth.
The catastrophists of Lyell's day, Gould nevertheless maintains, were right all along. The literal fossil evidence of major rapid changes in previous faunas does not need to be interpreted away, as Lyell tried to do by appealing to the imperfection of the geological record.
Gould sees supreme irony in the recent hypothesis of the Berkeley scientists Luis and Walter Alvarez that mass extinctions were caused by asteroidal or cometary impacts (a hypothesis now made plausible by the discovery of a worldwide iridium layer deposited at the Cretaceous-Tertiary boundary); for this is precisely the sort of wild "cosmological" speculation that Lyell derided in seventeenth-century writers like William Whiston.
Gould concludes Time's Arrow, Time's Cycle by insisting that arrows and cycles are "eternal metaphors" in the understanding of time. In a thoughtful complement to his discussion of the history of geology, he shows how these two metaphors have figured in the art and sculpture associated with major biblical themes. Both metaphors, he concludes, are needed "for any comprehensive view of history."
Sir Charles Lyell, 1st Baronet, was a Scottish geologist who demonstrated the power of known natural causes in explaining the earth's history. He is best known today for his association with Charles Darwin and as the author of Principles of Geology (1830–33), which presented to a wide public audience the idea that the earth was shaped by the same natural processes still in operation today, operating at similar intensities. The philosopher William Whewell termed this gradualistic view "uniformitarianism" and contrasted it with catastrophism, which had been championed by Georges Cuvier and was better accepted in Europe. The combination of evidence and eloquence in Principles convinced a wide range of readers of the significance of "deep time" for understanding the earth and environment.
Gradualism, from the Latin gradus ("step"), is a hypothesis, a theory or a tenet assuming that change comes about gradually or that variation is gradual in nature and happens over time as opposed to in large steps. Uniformitarianism, incrementalism, and reformism are similar concepts.
James Hutton was a Scottish geologist, agriculturalist, chemical manufacturer, naturalist and physician. Often referred to as the "Father of Modern Geology," he played a key role in establishing geology as a modern science.
Uniformitarianism, also known as the Doctrine of Uniformity or the Uniformitarian Principle, is the assumption that the same natural laws and processes that operate in our present-day scientific observations have always operated in the universe in the past and apply everywhere in the universe. It refers to invariance in the metaphysical principles underpinning science, such as the constancy of cause and effect throughout space-time, but has also been used to describe spatiotemporal invariance of physical laws. Though an unprovable postulate that cannot be verified using the scientific method, some consider that uniformitarianism should be a required first principle in scientific research. Other scientists disagree and consider that nature is not absolutely uniform, even though it does exhibit certain regularities.
Neptunism is a superseded scientific theory of geology proposed by Abraham Gottlob Werner (1749–1817) in the late 18th century, who proposed that rocks formed from the crystallisation of minerals in the early Earth's oceans.
In geology, catastrophism theorises that the Earth has largely been shaped by sudden, short-lived, violent events, possibly worldwide in scope. This contrasts with uniformitarianism, according to which slow incremental changes, such as erosion, brought about all the Earth's geological features. The proponents of uniformitarianism held that the present was "the key to the past", and that all geological processes throughout the past resembled those that can be observed today. Since the 19th-century disputes between catastrophists and uniformitarians, a more inclusive and integrated view of geologic events has developed, in which the scientific consensus accepts that some catastrophic events occurred in the geologic past, but regards these as explicable as extreme examples of natural processes which can occur.
Deep time is a term introduced and applied by John McPhee to the concept of geologic time in his book Basin and Range (1981), parts of which originally appeared in the New Yorker magazine.
Historical geology or palaeogeology is a discipline that uses the principles and methods of geology to reconstruct the geological history of Earth. Historical geology examines the vastness of geologic time, measured in billions of years, and investigates changes in the Earth, gradual and sudden, over this deep time. It focuses on geological processes, such as plate tectonics, that have changed the Earth's surface and subsurface over time and the use of methods including stratigraphy, structural geology, paleontology, and sedimentology to tell the sequence of these events. It also focuses on the evolution of life during different time periods in the geologic time scale.
Day-age creationism, a type of old Earth creationism, is an interpretation of the creation accounts in Genesis. It holds that the six days referred to in the Genesis account of creation are not ordinary 24-hour days, but are much longer periods. The Genesis account is then reconciled with the age of the Earth. Proponents of the day-age theory can be found among both theistic evolutionists, who accept the scientific consensus on evolution, and progressive creationists, who reject it. The theories are said to be built on the understanding that the Hebrew word yom is also used to refer to a time period, with a beginning and an end and not necessarily that of a 24-hour day.
Flood geology is a pseudoscientific attempt to interpret and reconcile geological features of the Earth in accordance with a literal belief in the global flood described in Genesis 6–8. In the early 19th century, diluvial geologists hypothesized that specific surface features provided evidence of a worldwide flood which had followed earlier geological eras; after further investigation they agreed that these features resulted from local floods or from glaciers. In the 20th century, young-Earth creationists revived flood geology as an overarching concept in their opposition to evolution, assuming a recent six-day Creation and cataclysmic geological changes during the biblical flood, and incorporating creationist explanations of the sequences of rock strata.
The Genesis Flood: The Biblical Record and its Scientific Implications is a 1961 book by young Earth creationists John C. Whitcomb and Henry M. Morris that, according to Ronald Numbers, elevated young Earth creationism "to a position of fundamentalist orthodoxy."
Plutonism is the geologic theory that the igneous rocks forming the Earth originated from intrusive magmatic activity, with a continuing gradual process of weathering and erosion wearing away rocks, which were then deposited on the sea bed, re-formed into layers of sedimentary rock by heat and pressure, and raised again. It proposes that basalt is solidified molten magma. The theory lead to plutonic (intrinsic) rock classification, which includes intrinsic igneous rocks such as gabbro, diorite, granite and pegmatite. The name plutonism references Pluto, the classical ruler of the underworld and the Roman god of wealth. A main reason Pluto was incorporated into the classification was due to the plutonic rocks commonly being present in gold and silver ore deposits (veins).
Siccar Point is a rocky promontory in the county of Berwickshire on the east coast of Scotland. It is famous in the history of geology for Hutton's Unconformity found in 1788, which James Hutton regarded as conclusive proof of his uniformitarian theory of geological development.
The history of geology is concerned with the development of the natural science of geology. Geology is the scientific study of the origin, history, and structure of Earth.
Principles of Geology: Being an Attempt to Explain the Former Changes of the Earth's Surface, by Reference to Causes Now in Operation is a book by the Scottish geologist Charles Lyell that was first published in 3 volumes from 1830–1833. Lyell used the theory of uniformitarianism to describe how the Earth's surface was changing over time. This theory was in direct contrast to the geological theory of catastrophism.
Sir Henry Hoyle Howorth was a British Conservative politician, barrister and amateur historian and geologist.
A geologist is a scientist who studies the solid, liquid, and gaseous matter that constitutes Earth and other terrestrial planets, as well as the processes that shape them. Geologists usually study geology, earth science, or geophysics, although backgrounds in physics, chemistry, biology, and other sciences are also useful. Field research is an important component of geology, although many subdisciplines incorporate laboratory and digitalized work. Geologists can be classified in a larger group of scientists, called geoscientists.
The discovery of human antiquity was a major achievement of science in the middle of the 19th century, and the foundation of scientific paleoanthropology. The antiquity of man, human antiquity, or in simpler language the age of the human race, are names given to the series of scientific debates it involved, which with modifications continue in the 21st century. These debates have clarified and given scientific evidence, from a number of disciplines, towards solving the basic question of dating the first human being.
Theory of the Earth was a publication by James Hutton which laid the foundations for geology. In it he showed that the Earth is the product of natural forces. What could be seen happening today, over long periods of time, could produce what we see in the rocks. It also hypothesized that the age of the Earth was much older than what biblical literalists claim. This idea, uniformitarianism, was used by Charles Lyell in his work, and Lyell's textbook was an important influence on Charles Darwin. The work was first published in 1788 by the Royal Society of Edinburgh, and later in 1795 as two book volumes.
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