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LibraryThing: Science in Ancient Mesopotamia Week 6: Roman Science

Augustine, 354-430 AD

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Augustine, City of God ()Augustine provides another example, along with Basil and Philoponos, of an emerging theistic perspective on nature. We have already looked at Basil, one of the most influential church fathers in the eastern, Greek-speaking areas of the Roman empire. Here we will turn to Augustine, the most influential church father in the western, Latin-speaking areas of the Roman empire. Augustine exerted a formative influence upon medieval and early modern culture, and his significance for intellectual history cannot be ignored. Let me share a personal anecdote: During a class held in the History of Science Collections in the fall of 1987, then-Curator Duane H.D. Roller wagged his finger at several of us who were just beginning our graduate studies in OU's history of science program and told us we had to read two works of theology if we wanted to understand the origins of modern science. The first of these was Augustine, De civitate Dei. Eventually I took Prof. Roller's advice by reading Augustine, and not only The City of God but also several of his other works. Indeed, the philosophical theology of Augustine played a crucial role in shaping the intellectual climate of medieval and early modern Europe. Augustine's complex and gigantic influence defies easy summary, and it is inextricably bound up with his philosophical theology, but this web page will identify a few of Augustine's contributions to the western tradition of natural science.

Christian Platonism

Before his conversion to Christianity, Augustine was one of the greatest Neoplatonists of the day. Although he came to differ from the Neoplatonists in many ways, yet wherever the influence of Augustine was felt, so Plato and Neoplatonism also became known. One of the consequences for the history of science is that Augustine continued the Platonic emphasis upon mathematics as a half-way house for the ascent of the soul.


Augustine is often hailed as the founder of psychology because of the intense exploration of selfhood that is captured in his Confessions. No previous writer had written in such a self-revealing way. His soul-searching created an inner dialogue, or soliloquy (conversation with oneself), a word which he invented to describe one's engagement with love, grief, longing and memory in this private inner world. Many scholars regard Augustine's Confessions as the first psychological autobiography, the ancestor of the modern novel. Augustine's concept of persons as capable of this private inner dialogue proved foundational for the western intellectual tradition. It was rooted in his theological discussions where, unlike Plato's demiurge or Aristotle's prime mover, Augustine's divinity was personal, and human beings were made personal in that image. For Augustine, ultimate reality is love. The one God is personal in the richest possible sense, consisting of three Persons in loving relationship from all eternity. In ultimate reality there is both unity and loving variety. Created personal in that image, human beings also are capable of a rich inner dialogue. Before Augustine, the word "persona" referred to a mask worn by an actor on stage, and represented the external role they would play. In contrast, because of Augustine's emphasis on the private inner world many scholars, like Phillip Cary (cited at the bottom of the page), regard Augustine as the originator of the modern concept of personhood.

Creatio ex nihilo: The contingent character of being

Previous natural philosophers such as Parmenides or Aristotle regarded nature as a necessary being. We have seen that Basil and other early theists regarded the natural order as contingent. Augustine took the idea of the contingency of nature even further.

We already mentioned Augustine in our unit on the presocratics when we saw that Parmenides argued for the eternity of the world and universe. Parmenides asked "how can what is, come to be from what is not?" For Parmenides, what exists is necessary being, constant and unchanging. Augustine answered Parmenides by saying that the deity created all that is from nothing (creatio ex nihilo) by his omnipotent power. This conception of an omnipotent Creator went far beyond not only Parmenides, but also Plato and Aristotle. For example, Plato's demiurge tried to impose forms on pre-existing, recalcitrant matter. For Augustine, Plato's old craft metaphor for the demiurge was drastically insufficient:

“For the power and might of the Creator... makes every creature abide; and if this power ever ceased to govern creatures, their essences would pass away and all nature would perish. When a builder puts up a house and departs, his work remains in spite of the fact that he is no longer there. But the universe will pass away in the twinkling of an eye if God withdraws his ruling hand.” Literal Meaning of Genesis

For Augustine, our very existence hangs by a thread. Due to the contingency of our being, we are continually dangling over the brink of annihilation.

“believe and if possible understand that God is working even now, so that if His action should be withdrawn from his creatures, they would perish.... God moves his whole creation by a hidden power and all creatures are subject to this movement: the angels carry out his commands, the stars move in their courses, the winds blow now this way now that, deep pools seethe beneath tumbling waterfalls and mists form above them, meadows come to life as the seeds put forth grasses, animals are born and live their lives according to their proper instincts, the evil are permitted to try the just. It is thus that God unfolds the generations which he laid up in creation when he first founded it; and they would not be sent forth to run their course if he who made creatures ceased to exercise his provident rule over them.” Literal Meaning of Genesis

Whereas for Aristotle the natures of things necessarily cause them to change, for Augustine even those natures would cease to exist if left on their own. Contrary to Aristotle, the natures of things are radically contingent, created from nothing by an omnipotent power outside themselves, rather than being self-caused or providing the explanation for their own existence.

From Augustine's theistic perspective, the constantly changing character of creation signifies that it is radically contingent rather than self-existing. Creation therefore points to a transcendent ground of existence. Romano Guardini explains that for Augustine:

“the existing order of things, indeed of life itself seems but loosely, precariously balanced across the chaos of existence and its uncontrollable forces. All rules seem temporary, and threaten to give way at any moment. Things themselves appear now shadowy, now ominous. Reality is by no means as substantial as it may seem, and personal existence, like all existence, is surrounded by and suspended over the powerful and perilous void.”

For Augustine, humans lean even farther over this chasm of nonbeing than sister nature because of our mutability, the capacity to change our natures for the worse. When we are corrupted by power or temptation we lapse into a relative lack of being. All creatures are radically insufficient and live in a dynamic history, continually dependent on their Creator.

Augustine, City of God (1489), frontispiece.The ancient Big Bang: Augustine's answer to Parmenides on the eternity of the world

In addition to arguments for the eternity of the world based on the necessary character of being (recapped above), Parmenides employed the principle of sufficient reason to ask: What would then have stirred being into activity that it should arise from not-being later rather than earlier? Imagine a timeline with points A, B and C:

Suppose that the universe had been created at time B. Why should the universe come to be at time B, rather than at time A or C? If there were a sufficient reason for it to come to be at time B, then the very same reason should have caused it to be at time A and time C, because before the creation of anything, times A, B and C were indistinguishable. Therefore, if the universe exists at any point in time, then it will have existed forever and will continue to exist forever. In other words, either the universe is eternal or its cause is irrational. This argument of Parmenides for the eternity of the universe based on the principle of sufficient reason proved compelling to Aristotle and other natural philosophers until Augustine.

Augustine responded by making space and time a part of the creation. The creation did not occur within space, or within a timeline, as if space and time were "containers" for the act of creation. Rather, creation included the origination of the spatial and temporal containers themselves. Time itself is part of the creation: “the world was made not in time but together with time.” Augustine explained:

"But why did it please the eternal God to create heaven and earth at that special time, seeing that He had not done so earlier? .... Now, it does not follow that it was by chance rather than by a divine reason that God localized the world in this spot instead of in another, even though no human reason can comprehend the divine reason and although this particular place has no special merit that it should be chosen in preference to an infinite number of others. Nor, in the same way, does it follow that we should suppose that it was by accident that God created the world at that specific time rather than before, even though previous times had been uniformly passing by throughout an infinite past and there was no difference which would cause this time to be chosen in preference to another.... it is silly to excogitate a past time during which God was unoccupied, for the simple reason that there was no such thing as time before the universe was made." City of God, XI.4-6, trans. G.G. Walsh

In other words, for Augustine there was a first moment of time, before which time did not exist.

Augustine's conception that time and space comprise an inextricable part of the creation tantalized cosmologists and physicists for two millennia. When Einstein's general relativity theory led him to suspect that the universe began in a "Big Bang," that is, in a singularity whereby even time and space came into existence along with matter and energy and physical laws, some of Einstein's friends feared that he had fallen into the hands of priests. From its formulation, Big Bang cosmology was perceived as confirming a basically Augustinian conception of creation. The following quotation from cosmologist Robert Jastrow is typical in this respect:

"At this moment it seems as though science will never be able to raise the curtain on the mystery of creation. For the scientist who has lived by his faith in the power of reason, the story ends like a bad dream. He has scaled the mountains of ignorance; he is about to conquer the highest peak; as he pulls himself over the final rock, he is greated by a band of theologians who have been sitting there for centuries." Robert Jastrow, God and the Astronomers (1978)

The "band of theologians" alluded to are, of course, the Augustinians.

Science and Biblical interpretation -- commentaries on Genesis and the hexameral tradition.

We have already noted with Basil that commentaries on Genesis, particularly "hexamera" or commentaries on the six days of creation, became an important genre of scientific writing through the middle ages and into the 17th century. Augustine himself wrote five different commentaries on the six days: in the Confessions, the City of God, in a longer work entitled The Literal Meaning of Genesis, and two other shorter works. For this reason, we may use Augustine as an example of how Christian theologians were able to engage in open-ended scientific explorations of origins without being bound to particular interpretations of the biblical text. Let's briefly list just a few principles of biblical interpretation espoused by Augustine:

1. Days of Creation not ordinary days

While many patristic commentators, such as Basil, interpreted the creation days as six 24-hour days, Augustine warned that the interpretation of the days of creation was extremely difficult, and argued that the text could not be read as if they were ordinary days. The days lie “beyond the experience and knowledge of us mortal earthbound men,” he cautioned, so that when comparing them to ordinary days “we must bear in mind that these [ordinary] days indeed recall the days of creation, but without in any way being really similar to them”; Literal Meaning of Genesis, Bk. IV, ch. 27; 1:135.

2. Principle of Multiple Interpretations

Augustine sanctioned natural explanations of biblical events such as the creation so long as one allowed for the existence of multiple competing hypotheses instead of tying the biblical account to only one physical interpretation:

"In matters that are obscure and far beyond our vision, even in such as we may find treated in Holy Scripture, different interpretations are sometimes possible without prejudice to the faith we have received. In such a case, we should not rush in headlong and so firmly take our stand on one side that, if further progress in the search of truth justly undermines this position, we too fall with it. That would be to battle not for the teaching of Holy Scripture but for our own, wishing its teaching to conform to ours, whereas we ought to wish ours to conform to that of Sacred Scripture." Literal Meaning of Genesis, Bk. I, ch. 18; 1:41; cf. Bk. I, ch. 19; 1:41-42.

Augustine consistently offered physical interpretations provisionally, and suggested alternatives whenever possible.

3. Principle of the Unity of Truth

Augustine assumed a unity of truth, whether learned from scripture or from nature. This means that both scripture and science are of equal authority, and must be interpreted so that they are in agreement. Where the Bible states propositions of possible relevance to natural philosophy, these must be interpreted consistently with natural knowledge. Because the two books of nature and scripture share the same divine author, they may not be read with conflicting interpretations. Augustine cautioned that when defending a possible interpretation

“we should always observe that restraint that is proper to a devout and serious person and on an obscure question entertain no rash belief. Otherwise, if the evidence later reveals the explanation, we are likely to despise it because of our attachment to our error, even though this explanation may not be in any way opposed to the sacred writings....” Literal Meaning of Genesis, Bk. II, ch. 18; 1:73.

We shall see that Galileo quoted Augustine when he explained that scripture never errs, but its interpreters do.

4. Principle of Accommodation

Augustine taught that the language of scripture was accommodated to the understanding of ordinary readers because it was not intended to teach the theories of natural science. The principle of accommodation does not suggest that physical statements in scripture are false, but that their language is not philosophical or technical. Concerned that some might jeopardize the credibility of scripture by mis-interpreting its physical statements, Augustine warned that

“in the matter of the shape of heaven the sacred writers knew the truth, but that the Spirit of God, who spoke through them, did not wish to teach men these facts that would be of no avail for their salvation.” Literal Meaning of Genesis, Bk. II, ch. 9; 1:59.

Ernan McMullin explains Augustine’s principle of accommodation: “Moses could not have been expected to make his narrative conform to the truths of natural philosophy since this would have confused his uneducated readers. The task of the theologian, therefore, was to reinterpret in the light of the best natural knowledge of the day the texts thus accommodated. And the norms governing this reinterpretation were to be quite generous.” Ernan McMullin, ed., Evolution and Creation (South Bend: Notre Dame University Press, 1985) p. 20.

5. Principle of Phenomenalism

According to the principle of phenomenalism, the original writers of scripture accommodated their physical statements to the capacities of ordinary people by simply describing sensible phenomena as they would appear to any observer. Therefore physical references should be interpreted as entailing only those things that are immediately obvious to the senses. The principle of phenomenalism means that the sacred writers adapted scripture to refer to obvious phenomena in a common-sense manner, avoiding allusions to hidden causes or bits of secret knowledge that would only confuse the uneducated.

For example, Genesis 1:16 refers to the creation of the "two great lights -- the greater light to govern the day and the lesser light to govern the night. He also made the stars." Does this teach that the Moon is larger than the stars, since the stars are not among the "great lights"? Augustine suspected that the stars were indeed small enough to be set in diurnal rotation by the rays of the Sun, but nevertheless he insisted that this verse teaches nothing about the Moon’s actual size. Rather, adopting a principle of phenomenalism, Augustine affirmed that it only referred to the relative appearance of the Moon and stars to the eye. Literal Meaning of Genesis, Bk 2, ch. 16, 1:69-71.

Another example is whether the alternation of day and night in Genesis 1 contradicts the sphericity of the Earth, since day and night continuously and simultaneously exist opposite each other on the globe. Augustine denied that the language of scripture was relevant for the shape of the Earth because the alternating day and night were described from the perspective of an observer at a specific location on the surface of the globe. (This commentary is one of the clearest places where Augustine affirmed the sphericity of the globe.) Literal Meaning of Genesis, Bk 1, ch. 12, 1:33.

Thus phenomenalist interpretations of the literal meaning of physical statements in scripture render them of little or no use in natural philosophy.

Although the relations between the history of science and biblical interpretation are far more complex than this brief survey suggests, these five principles (days not ordinary days, multiple possible interpretations, unity of truth, accommodation, phenomenalism), and important variations in when and how they were applied, provided more versatile resources for future scientists to adapt literal interpretations of scripture to new physical interpretations than is recognized, even before the widespread acceptance of biblical criticism.

Temporal contingency: Augustine's vision of a linear history

Pagan perspectives of time tended to be cyclical (cf. Mircea Eliade, The Myth of the Eternal Return). In contrast, Augustine's City of God stands as the classic formulation of a conception of linear history. We have seen that Basil adapted Stoic cycles to fit them into a linear historical framework, but Augustine went further by arguing that history consists of unique and utterly novel events.

As the Roman empire was crumbling all around, Augustine argued against fatalism by offering a profound view of historical significance. The end of the empire was not the end of the world or cause for despair. Arguing against the idea of infinite cosmic cycles and the eternity of human existence, in the City of God Augustine affirmed that by his will God could “keep on endlessly creating one new and dissimilar thing after another.”

We have seen that for Augustine the world is not a necessary, self-existing being; it had a beginning and was created from nothing. For Augustine, the temporal succession of events also occurs neither by chance nor by necessity. Time became a creature, our sister, like nature. As a consequence, the present becomes a unique, contingent moment. The present moment is unique, rather than a point in an eternally recurring cycle. The present moment is contingent, in that it might have been otherwise. Yet the present moment is also intelligible, even though it is unique and utterly novel.

Augustine's vision of linear history was hugely influential, not only for western ideas of history and progress, but also for the eventual development of the historical sciences (next section).

Seminales rationes: spontaneous generation and evolution

In the Literal Meaning of Genesis, Augustine explained that at the creation God implanted "rational seeds" (rationes seminales), which would develop over time into the products of creation. In other words, the potential for all natural things was created in the beginning, but not all things have existed since the beginning. Rather, many natural things developed over time in a historical unfolding of the natural order.

Augustine’s idea of implanted rational seeds imparted a developmental aspect to nature. In later centuries this developmental aspect allowed for an understanding of spontaneous generation (the generation of insects and other lower forms of life from non-life) as due not to chance but to the rational seeds and purpose of the Creator. In the 19th century, the Christian reception of Darwin's theory of evolution of species by means of natural selection was greatly facilitated by Augustinian views of rational seeds (see the works by Messenger and McKeough, cited below).


Augustine's influence upon the history of medieval and early modern western science was incalculably immense. He viewed faith and reason as engaged in a continuing conversation, rather than being contradictory or isolated from each other. He insisted that all truth is God's truth and that Christians should not fear the discoveries of unbelievers about the natural order, but accept them as the "plunder of the Egyptians" given to the Hebrews in the Exodus. These and the other aspects of his influence discussed above merely scratch the surface.

Dive Deeper

The Christian Classics Ethereal Library provides the Confessions, the City of God and other works by Augustine.

Augustine, The Literal Meaning of Genesis, trans. John Hammond Taylor, 2 vols., Ancient Christian Writers, nos. 41–42. (New York: Newman Press, 1982).

David C. Lindberg, “Science and the Early Church.” in God and Nature, ed. David C. Lindberg and Ronald L. Numbers (Berkeley: University of California Press, 1986), pp. 19-48.

Henry Chadwick, Augustine: A Very Short Introduction (Oxford, 2001). Excellent brief introduction; Chadwick also published a respected translation of Augustine's Confessions.

Ernest C. Messenger, Evolution and Theology: The Problem of Man’s Origin (New York: MacMillan, 1932) and Michael J. McKeough, The Meaning of Rationes Seminales in St. Augustine (Washington, D.C.: Catholic University of America, 1926). These two classic studies demonstrate the significance of Augustine's thought for the acceptance of evolutionary ideas.

Ernan McMullin, ed., Evolution and Creation (South Bend: Notre Dame University Press, 1985).

Francis Oakley, Omnipotence, Covenant and Order (Cornell University Press, 1984). An influential scholarly survey of the implications of the doctrine of divine omnipotence for the history of ideas.

Phillip Cary, Augustine's Invention of the Inner Self (Oxford: Oxford University Press, 2003).

Phillip Cary, Augustine: Philosopher and Saint, 12 lectures for audio download through The Teaching Company. This is an excellent overview of Augustine's significance for intellectual history.


"Give me chastity and continence, but not quite yet."
"The world is a book, and those who do not travel read only a page."
"This is the very perfection of a man, to find out his own imperfections."
"Indeed, man wishes to be happy even when he so lives as to make happiness impossible."
"Love, and do as you like."
"Men go abroad to wonder at the heights of mountains, at the huge waves of the sea, at the long courses of the rivers, at the vast compass of the ocean, at the circular motions of the stars, and they pass by themselves without wondering."
-- Augustine

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HSCI 3013. History of Science to 17th centuryCreative Commons license
Kerry Magruder, Instructor, 2004
Brent Purkaple, TA

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Many thanks to the pedagogical model developed in Mythology and Folklore and other online courses by Laura Gibbs, which have been an inspiration for this course.

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