Religion and Science

Ian G. Barbour

• Publisher: HarperOne
• Year: 2013
• ISBN:
  9780062277213
• Topic: Theology & Religion
• Subtopic: Religion

Religion and Science is a definitive contemporary discussion of the many issues surrounding our understanding of God and religious truth and experience in our understanding of God and religious truth and experience in our scientific age. This is a significantly expanded and feshly revised version of Religion in an Age of Science, winner of the American Academy of Religion Award for Excellence and the Templeton Book Award. Ian G. Barbour--the premier scholar in the field--has added three crucial historical chapters on physics and metaphysics in the seventeenth century, nature and God in the eighteenth century, and biology and theology in the nineteenth century. He has also added new sections on developments in nature-centered spirituality, information theory, and chaos and complexity theories.

Part One

RELIGION AND THE HISTORY OF SCIENCE

CHAPTER 1

Physics and Metaphysics in the Seventeenth Century

The seventeenth century was a period of such crucial and rapid change in outlook that we may justifiably speak of it as marking the birth of modern science. Two landmarks in the growth of the new science were Galileo’s Dialogue (1632) and Newton’s Principia (1687). The lives of these two persons also provide illuminating examples of the interactions between science and religion that are our concern. It was in the physical sciences that the new intellectual climate first captured the human imagination and became the basis for a new world view. To see the extent of the transition wrought, we will start by outlining some assumptions of the Middle Ages that were challenged in the seventeenth century. We look successively at “The Medieval World-Drama,” “Galileo’s ‘Two New Sciences,’” and “The Newtonian World-Machine.”

Our objective is to analyze how views of God and human nature were affected by the new methods of inquiry in science and the new scientific understanding of nature. We will indicate briefly the approaches taken by Aquinas, by Galileo, and then by Newton, to the following topics: (1) methods in science, (2) the character of nature, (3) methods in theology, (4) God’s relation to nature, and (5) human nature. The final section of the chapter examines the positive contributions of religious thought to the rise of science and the major points of conflict.

In some cases, specific scientific theories, such as the Copernican theory that the sun rather than the earth is the center of the planetary system, seemed to conflict with traditional religious ideas. But science also influenced religious thought indirectly by calling philosophical assumptions into question, especially those in epistemology (analysis of methods of inquiry and theories of knowledge) and metaphysics (analysis of the most general characteristics of reality; see Glossary for definitions of frequently used specialized terms). We will be considering both direct and indirect influences of the new science on views of nature, God, and humanity.

These chapters of historical background do not try to describe all the complex factors in the growth of modern thought in either science or religion. In each field new ideas were the product, not of isolated individuals, but of communities of inquiry within wider cultural contexts. The social history of both science and religion is as important as an account of “great scientists” or “important theologians.” However, the discussion of a few pivotal figures in their social contexts can serve to illuminate the origins of contemporary issues.

I. THE MEDIEVAL WORLD-DRAMA

Amid the rich diversity of the Middle Ages, Thomas Aquinas (1225–1274) stands out as the most systematic and influential medieval author. His synthesis of Christian theology and Aristotelian philosophy articulated a distinctive approach to both science and religion that dominated Western thought until the seventeenth century. Let us consider his views on each of our five topics.

1. METHODS IN SCIENCE: EXPLANATION BY PURPOSES

During the 1950s and 1960s, several widely read books by historians of science portrayed the radical character of the “scientific revolution” of the seventeenth century and claimed that the Middle Ages made no substantial contributions to science.1 More recently, specialists in the history of medieval science have made detailed studies of particular people and topics. They insist that medieval authors must be examined in the context of their own times and that significant advances were made in medicine, technology, and physics. They point to continuity as well as discontinuity between medieval and early modern science. For example, Galileo’s concept of inertial momentum had a precursor in the writings of Jean Buridan and Nicole Oresme at the University of Paris in the fourteenth century, namely their idea of “impetus” as the cause of continuing motion.2

Yet even these recent authors acknowledge that medieval science was carried out within an Aristotelian framework with goals very different from those of Galileo and his successors. Medieval writers were primarily interested in the logical relationships among ideas, and only secondarily were they interested in testing hypotheses by experiments. I will argue that modern science really does represent a revolution in methods of inquiry, so that ideas with forerunners in earlier centuries were used in a new way. Creek science was recovered when the writings of Aristotle were translated from Arabic in the thirteenth century. From 1250 to 1650, Aristotle was the core of the curriculum in the universities of western Europe. Science was not an autonomous profession but a branch of philosophy, and Aristotle’s Physics was widely read and discussed—and challenged, even though its basic assumptions were still accepted.

For what type of explanation of an event should one search? To what sort of questions about nature is it most important to seek answers? Aristotle sought explanations in terms of the true form or intelligible essence of an object and the purpose it fulfills. Why do objects fall? For Aristotle and his followers, motion is explained by the tendency of each thing to seek its own natural resting place. The “natural place” of fire is up, and that of earth is down. The end of the motion—in the sense both of terminus and of purpose—was of more interest than the intervening process. Why does an acorn grow? To become an oak. Why is there rain? To nourish plants. Causality is described by future goals (“final causes”) and innate tendencies (“formal causes”), not just by the effects of past events (“efficient causes”) acting on objects in the present (“material causes”). The future goal need not be consciously entertained by an entity (for example, an acorn) but is built into its structure so that by its own nature it achieves the fulfillment of the end appropriate to its kind by the expression of form through matter.3

Attention was directed to the final end and not to the detailed process of change from moment to moment. The behavior of each creature follows from its essential nature. If every creature realizes its potentialities, the most illuminating questions are those concerning the uses of things and what they can do. The central feature of all change, in this view, is the transformation of potentiality into actuality. Logical connections, not simply temporal ones, must be traced. The categories of explanation are essence and potentiality, not mass and motion connected by laws in space and time. In the Middle Ages, this search for purposes was also the result of conceiving every object as having a place in a cosmic hierarchy, the creation of a purposeful God. God’s purposes in creating things, though not always discernible, constitute the ultimate explanation of their behavior.4

Because of this assumption of the rationality of the universe, both Greek and medieval science were primarily deductive (starting from necessary general principles and reasoning to particular exemplifications of those principles) rather than inductive (starting from particular observations and generalizing from them). This preference for deductive logic was closely related to the classical idea, particularly prominent in Plato, that knowledge is contemplation of the perfect forms of eternal truth rather than observation of their imperfect embodiment in the changing world. The way a thing behaves was also linked with its status in the overall scheme. The goal was not primarily, as in modern science, the description, prediction, and control of a limited phenomenon but rather the understanding and contemplation of the meaning of the part in relation to the whole and to God.

This does not mean that observation was absent from Aristotelian and medieval science. Many of Aristotle’s conclusions were in conformity with common experience. He had done considerable biological classification, for example, which required careful observation. But the categories of teleology (purpose) did not in general lend themselves to theories that could be tested by further experiment. We shall see that Galileo deliberately set aside all questions of purpose and “final cause” and introduced a totally different kind of concept tied to measurable relationships between observable phenomena.

2. NATURE AS A CREATED HIERARCHY

Aristotelian cosmology and Christian theology were merged to form the medieval picture of the universe. Earth was a fixed central sphere surrounded by the concentric spheres of the heavens. The planets, in the Ptolemaic theory, followed circles whose centers were attached to moving spheres; heavenly objects, being perfect and incorruptible, were said to make use only of the perfect form, the circle. This geocentric (earth-centered) scheme was easily visualized and corresponded to the commonsense experience of the solidity of the earth. Here position and destiny coincided. Humanity was unique and central in both location and importance; the divine was more perfect and comprehensive, separated both geographically and metaphysically from the created order. Within this overall pattern, every entity from greatest to least had its status and purpose in the graded hierarchy of reality: God, planets, angels, men, women, animals, and plants. Everything was in its neatly arranged place in an integrated total plan. It was a law-abiding world, but the laws were moral and not mechanical. This was the medieval view of the universe that the new science would call into question.

A wide variety of attitudes toward nature was expressed during the Middle Ages. At times spiritual destiny seemed so to outweigh temporal relationships that the world was treated as a great allegory whose essential secret was its religious meaning, not its operation or its causes. Symbolic interpretations of nature were sometimes derived from ancient legends unrelated to any factual observations. At other times, particularly among the common people, nature seemed to be the seat of evil forces and demonic powers, as it had been to most of the late Greek (Hellenistic) world; it was to be a long struggle before science would be free from association with magic, sorcery, and astrology. To some people, the sense of God’s creation was overpowering; to St. Francis, for example, nature was a sacrament of the divine. For Aquinas and his followers, the conviction of God’s rationality encouraged an affirmative attitude toward nature, which, as we shall see, contributed indirectly to the rise of Science.

Medieval thought was in general realistic in the sense that it held the world to be real as perceived, experienced, and understood. The rational powers of the intellect were believed to be capable of grasping the true essence of the world. It was said that nature is immediately present to us and clearly intelligible to our minds. Color and warmth, love and purpose were taken as integral characteristics of existing beings. The possibility of knowledge of the external world was not seriously doubted, as it has been in modern philosophy since Descartes.

Note finally that nature was assumed to be essentially static, with all its species created in their present forms. It was a completed world in which there could be no fundamental novelty except as God acts in it. However, the life of each creature might include outward change and development as its God-given potentialities unfold. One might say that the basic image of nature was that of a Kingdom—a fixed , hierarchical, ordered society under a sovereign Lord.

3. METHODS IN THEOLOGY: REASON AND REVELATION

To understand some of the subsequent interactions of science and religion, we must briefly summarize the sources of authority in medieval theology. Scholastic thought was based on both reason and revelation, showing again the characteristic synthesis of elements from Greek philosophy and biblical faith. God is known through both natural and revealed theology. The natural truths are open to all people by the unaided powers of human reason; the revealed truths were disclosed by God through Christ and the prophets and are transmitted through scripture and tradition as preserved by the church. Since all truth is from God, the two basic sources will be consistent with each other.

In Aquinas’s system, reason is an important preamble to faith. It can establish some theological truths, including the existence of God. The teleological argument leads from the evidence of design in nature to the idea of an intelligent Designer. The cosmological argument moves from the contingency of the world to its necessary ground, a First Cause of all effects. God has been at least partially disclosed in the universe. But to Aquinas this natural theology remained secondary to revealed theology; it was not the main source of knowledge of God, as it was to be for many thinkers by the eighteenth century.5

Revelation is necessary, according to Aquinas, because the most important theological truths are not accessible to reason. God’s existence is rationally demonstrable, but the trinity and the incarnation are not. The divine plan of salvation was made known through the channels God chose to establish. Even those truths that can be proven philosophically have been made more readily available to the average person through revelation. Faith is thus primarily the acceptance of revealed truths on the authority of the church rather than (as for the Protestant Reformers) an attitude of trust and commitment in direct personal relationship to God as known in Christ. In medieval thought, the church is not only the channel of divine grace, mediated through Christ’s death and the efficacy of the sacraments, but also the channel of divine truth, imparted through Christ’s teaching and transmitted by the continuing community that was his chosen instrument.

The Bible was only one element in this total system of thought, and scripture was considered authoritative only as interpreted by the church. Moreover, the doctrine of “levels of truth” in the Bible allowed some flexibility for allegorical interpretation and poetic meaning. Scripture was thus only one issue in the conflict that arose between Galileo and the Catholic Church. Galileo’s defense of Copernican astronomy seemed to threaten an inclusive intellectual scheme that was strongly dependent on Aristotelian assumptions and on an institutional church that asserted its authority to interpret scripture.

4. GOD AS CREATOR AND REDEEMER

In Aquinas’s conception of God, Aristotle’s Unmoved Mover and the Bible’s personal Father had become one. The metaphysical First Cause of Greek philosophy was identified with the dynamic purposeful Creator of biblical theology. Though at times the more abstract philosophical attributes (omniscience, omnipotence, omnipresence, eternity) may seem to have predominated over more personalistic biblical images (father, judge, savior), Aquinas’s writing clearly pictures a God who is concerned about human redemption. We must here restrict ourselves to some comments on the Thomistic understanding of God’s relation to nature.

Aquinas presents one form of the cosmological argument: every event must have a cause, which in turn must be the effect of an earlier cause, and so forth, back to a First Cause. But Aquinas also considers the possibility of an infinite sequence of causes—an idea that is being discussed by some astronomers today. He maintains that the crucial feature of all events in the world, whether in a finite or an infinite series, is their contingency, the fact that they might not have occurred. Why is there anything rather than nothing? Every entity in the world is dependent on other entities, and all are sharply distinguished from God, a necessary being whose existence is not dependent on the existence of other beings. Aquinas also defends the argument from design; but the argument did not exclu...

Table of contents

• Contents
• Preface
• Introduction
• PART ONE: RELIGION AND THE HISTORY OF SCIENCE
• PART TWO: RELIGION AND THE METHODS OF SCIENCE
• PART THREE: RELIGION AND THE THEORIES OF SCIENCE
• PART FOUR: PHILOSOPHICAL AND THEOLOGICAL REFLECTIONS
• Notes
• Glossary
• Searchable Terms 1
• Searchable Terms 2
• About the Author
• Copyright
• About the Publisher