The philosophical exploration of religious beliefs and practices is evident in the earliest recorded philosophy, east and west. In the west, throughout Greco-Roman philosophy and the Medieval era, philosophical reflection on God, or gods, reason and faith, the soul, afterlife, and so on were not considered to be a sub-discipline called “philosophy of religion.” The philosophy of God was simply one component among many interwoven philosophical projects. This intermingling of philosophical inquiry with religious themes and the broader enterprises of philosophy (e.g. political theory, epistemology, et al.) is apparent among many early modern philosophers such as Thomas Hobbes, John Locke, and George Berkeley. Only gradually do we find texts devoted exclusively to religious themes. The first use of the term “philosophy of religion” in English occurs in the 17th century work of Ralph Cudworth. Cudworth and his Cambridge University colleague Henry More produced philosophical work with a specific focus on religion and so, if one insisted on dating the beginning of philosophy of religion as a field, there are good reasons for claiming that it began (gradually) in the mid- 17th century (see Taliaferro 2005). Much of the subject matter treated by Cudworth and More is continuous with the current agenda of philosophy of religion (arguments about God's existence, the significance of religious pluralism, the nature of good and evil in relation to God, and so on), and many of the terms that are in current circulation had their origin in Cudworth's and his colleague's work (they coined the terms theism, materialism,consciousness, et al.).
Today philosophy of religion is a robust, intensely active area of philosophy. Almost without exception, any introduction to philosophy text in the Anglophone world includes some philosophy of religion. The importance of philosophy of religion is chiefly due to its subject matter: alternative beliefs about God, Brahman, the sacred, the varieties of religious experience, the interplay between science and religion, the challenge of non-religious philosophies, the nature and scope of good and evil, religious treatments of birth, history, and death, and other substantial terrain. A philosophical exploration of these topics involves fundamental questions about our place in the cosmos and about our relationship to what may transcend the cosmos. Such philosophical work requires an investigation into the nature and limit of human thought. Alongside these complex, ambitious projects, philosophy of religion has at least three factors that contribute to its importance for the overall enterprise of philosophy.
Philosophy of religion addresses embedded social and personal practices. Philosophy of religion is therefore relevant to practical concerns; its subject matter is not all abstract theory. Given the vast percentage of the world population that is either aligned with religion or affected by religion, philosophy of religion has a secure role in addressing people's actual values and commitments. A chief point of reference in much philosophy of religion is the shape and content of living traditions. In this way, philosophy of religion may be informed by the other disciplines that study religious life.
Another reason behind the importance of the field is its breadth. There are few areas of philosophy that are shorn of religious implications. Religious traditions are so comprehensive and all-encompassing in their claims that almost every domain of philosophy may be drawn upon in the philosophical investigation of their coherence, justification, and value.
A third reason is historical. Most philosophers throughout the history of ideas, east and west, have addressed religious topics. One cannot undertake a credible history of philosophy without taking philosophy of religion seriously.
While this field is vital for philosophy, philosophy of religion may also make a pivotal contribution to religious studies and theology. Religious studies often involve important methodological assumptions about history and about the nature and limits of religious experience. These invite philosophical assessment and debate. Theology may also benefit from philosophy of religion in at least two areas. Historically, theology has often drawn upon, or been influenced by, philosophy. Platonism and Aristotelianism have had a major influence on the articulation of classical Christian doctrine, and in the modern era theologians have often drawn on work by philosophers (from Hegel to Heidegger and Derrida). Another benefit lies in philosophy's tasks of clarifying, evaluating, and comparing religious beliefs. The evaluation has at times been highly critical and dismissive, but there are abundant periods in the history of ideas when philosophy has positively contributed to the flourishing of religious life. This constructive interplay is not limited to the west. The role of philosophy in distinctive Buddhist views of knowledge and the self has been of great importance. Just as philosophical ideas have fueled theological work, the great themes of theology involving God's transcendence, the divine attributes, providence, and so on, have made substantial impacts on important philosophical projects. (Hilary Putnam, for example, has linked the philosophy of truth with the concept of a God's-eye point of view.)
At the beginning of the 21st century, a more general rationale for philosophy of religion should be cited: it can enhance cross-cultural dialogue. Philosophers of religion now often seek out common as well as distinguishing features of religious belief and practice. This study can enhance communication between traditions, and between religions and secular institutions.
4.1 Philosophical Reflection on Divine Attributes
Most philosophy of religion in the west has focused on different versions of theism. Ancient philosophy of religion wrestled with the credibility of monotheism and polytheism in opposition to skepticism and very primitive naturalistic schemes. For example, Plato argued that the view that God is singularly good should be preferred to the portrait of the gods that was articulated in Greek poetic tradition, according to which there are many gods, often imperfect and subject to vice and ignorance. The emergence and development of Judaism, Christianity, and Islam on a global scale secured the centrality of theism for philosophical enquiry, but the relevance of a philosophical exploration of theism is not limited to those interested in these religions and the cultures in which they flourish. While theism has generally flourished in religious traditions amid religious practices, one may be a theist without adopting any religion whatever, and one may find theistic elements (however piecemeal) in Confucianism, Hinduism, some versions of Mahayana Buddhism, as well as in the religions of some smaller scale societies. The debate over theism also has currency for secular humanism and religious forms of atheism as in Theravada Buddhist philosophy. Consider first the philosophical project of articulating theism and then the philosophy of divine attributes.
Terms applied both to God and to any aspect of the world have been classified as either univocal (sharing the same sense), equivocal (used in different senses), or analogical. There is a range of accounts of analogous predication, but the most common—and the one assumed here—is that terms are used analogously when their use in different cases (John limps and the argument limps) is based on what is believed to be a resemblance. It seems clear that many terms used to describe God in theistic traditions are used analogously, as when God is referred to as a father, shepherd, or fountain. More difficult to classify are descriptions of God as good, personal, knowing, omnipresent, and creative. Heated philosophical and theological disputes centre on unpacking the meaning of such descriptions, disputes that are often carried out with the use of thought experiments.
In thought experiments, hypothetical cases are described—cases that may or may not represent the way things are. In these descriptions, terms normally used in one context are employed in expanded settings. Thus, in thinking of God as omniscient, one might begin with a non-controversial case of a person knowing that a proposition is true, taking note of what it means for someone to possess that knowledge and of the ways in which the knowledge is secured. A theistic thought experiment would seek to extend our understanding of knowledge as we think of it in our own case, working toward the conception of a maximum or supreme intellectual excellence befitting the religious believers' understanding of God. Various degrees of refinement would then be in order, as one speculates not only about the extent of a maximum set of propositions known but also about how these might be known. That is, in attributing omniscience to God, would one thereby claim God knows all truths in a way that is analogous to the way we come to know truths about the world? Too close an analogy would produce a peculiar picture of God relying upon, for example, induction, sensory evidence, or the testimony of others. One move in the philosophy of God has been to assert that the claim “God knows something” employs the word “knows” univocally when read as picking out the thesis that God knows something, while it uses the term in only a remotely analogical sense if read as identifying how God knows (Swinburne 1977).
Here a medieval distinction comes into play between the res significata (what is asserted—for instance, that God knows X) and modus significandi (the mode or manner in which what is signified is realized or brought about—for instance, how God knows X). We might have a good grasp of what is meant by the claim that a being is omniscient while having little idea of how a being might be so. Thought experiments aimed at giving some sense to the Divine attribute of omniscience have been advanced by drawing attention to the way we know some things immediately (bodily positions, feelings and intentions), and then by extending this, coaxing us into conceiving a being that knows all things about itself and the cosmos immediately (see Beaty 1991 and Zagzebski 2008 for a constructive view, and Blumenfeld in Morris (ed.) 1987 for criticism).
Utilizing thought experiments and language in this way, philosophical theology has a stake in the soundness and richness of the imagination, picturing the way things might be “in one's mind's eye,” whether or not this relies on any actual imagery. Philosophers are now more cautious about drawing such inferences as we are increasingly aware of how some features of an imagined state of affairs might be misconceived or overlooked. Even so, it has been argued that if a state of affairs appears to one to be possible after careful reflection, checking it against one's background knowledge in other areas, then there is at least some warrant in judging the state of affairs to be a bona fide possibility (Sorensen 1992; see also Taliaferro 2002 and Gendler and Hawthorne 2002).
Work on the divine attributes has been vast. To generate a portrait of the literature on divine attributes, consider the issues that arise in reflection on omniscience, eternity, and goodness.
Imagine there is a God who knows the future free action of human beings. If God does know you will freely do some act X, then it is true that you will indeed do X. But if you are free, would you not be free to avoid doing X? Given that it is foreknown you will do X, it appears you would not be free to refrain from the act.
Initially this paradox seems easy to dispel. If God knows about your free action, then God knows that you will freely do something and that you could have refrained from it. God's foreknowing the act does not make it necessary. Does not the paradox only arise because we confuse the proposition, “Necessarily, if God knows X, then X” with “If God knows X, then necessarily X”? After all, it is necessarily the case that if I know you are reading this entry right now, then it follows that you are reading this entry, but your reading this entry may still be seen as a contingent state of affairs. But the problem is not so easily diffused, however, because if God does infallibly know that some state of affairs obtains then it cannot be that the state of affairs does not obtain. Think of what is sometimes called the necessity of the past. Once a state of affairs has obtained, it is unalterably or necessarily the case that it did occur. If the future is known precisely and comprehensively, isn't the future like the past, necessarily or unalterably the case? If the problem is put in first-person terms and one imagines God foreknows you will freely turn to a different entry in this Encyclopedia (moreover, God knows with unsurpassable precision when you will do so, which entry you will select and what you will think about it), then an easy resolution of the paradox seems elusive. To highlight the nature of this problem imagine God tells you what you will freely do in the next hour. Under such conditions, is it still intelligible to believe you have the ability to do otherwise if it is known by God as well as yourself what you will indeed elect to do? Self-foreknowledge, then, produces an additional related problem because the psychology of choice seems to require prior ignorance about what we will choose.
Various replies to the freedom-foreknowledge debate have been given. Some adopt compatibilism, affirming the compatibility of free will and determinism, and conclude that foreknowledge is no more threatening to freedom than determinism. While some prominent philosophical theists in the past have taken this route (most dramatically Jonathan Edwards in the eighteenth century), this seems to be the minority position in philosophy of religion today (exceptions include Paul Helm and Lynne Baker). A second position adheres to the libertarian outlook, which insists that freedom involves a radical, indeterminist exercise of power, and concludes that God cannot know future free action. What prevents such philosophers from denying that God is omniscient is that they contend there are no truths about future free actions, or that while there are truths about the future, God freely decides not to know them in order to preserve free choice. On the first view, prior to someone's doing a free action, there is no fact of the matter that he or she will do a given act. This is in keeping with a traditional, but controversial, interpretation of Aristotle's philosophy of time and truth. Aristotle may have thought it was neither true nor false prior to a given sea battle whether a given side would win it. Some theists, such as Richard Swinburne, adopt this line today, holding that the future cannot be known. If it cannot be known for metaphysical reasons, then omniscience can be analyzed as knowing all that it is possible to know. That God cannot know future free action is no more of a mark against God's being omniscient than God's inability to make square circles is a mark against God's being omnipotent. Other philosophers deny the original paradox. They insist that God's foreknowledge is compatible with libertarian freedom and seek to resolve the quandary by claiming that God is not bound in time (God does not so much foreknow the future as God knows what for us is the future from an eternal viewpoint) and by arguing that the unique vantage point of an omniscient God prevents any impingement on freedom. God can simply know the future without this having to be grounded on an established, determinate future. But this only works if there is no necessity of eternity analogous to the necessity of the past. Why think that we have any more control over God's timeless belief than over God's past belief? If not, then there is an exactly parallel dilemma of timeless knowledge. For outstanding current analysis of freedom and foreknowledge, see the work of Linda Zagzebski.
Could there be a being that is outside time? In the great monotheistic traditions, God is thought of as without any kind of beginning or end. God will never, indeed, can never, cease to be. Some philosophical theists hold that God's temporality is very much like ours in the sense that there is a before, during, and an after for God, or a past, present, and future for God. This view is sometimes referred to as the thesis that God is everlasting. Those adopting a more radical stance claim that God is independent of temporality, arguing either that God is not in time at all, or that God is “simultaneously” at or in all times. This is sometimes called the view that God is eternal as opposed to everlasting.
Why adopt the more radical stance? One reason, already noted, is that if God is not temporally bound, there may be a resolution to the earlier problem of reconciling freedom and foreknowledge. As Augustine put it: “For He does not pass from this to that by transition of thought, but beholds all things with absolute unchangeableness; so that of those things which emerge in time, the future, indeed, are not yet, and the present are now, and the past no longer are; but all of these are by Him comprehended in His stable and eternal presence” (The City of God, 1972, XI, 21). If God is outside time, there may also be a secure foundation explaining God's immutability (changelessness), incorruptibility, and immortality. Furthermore, there may be an opportunity to use God's standing outside of time to launch an argument that God is the creator of time.
Those affirming God to be unbounded by temporal sequences face several puzzles which I note without trying to settle. If God is somehow at or in all times, is God simultaneously at or in each? If so, there is the following problem. If God is simultaneous with the event of Rome burning in 410, and also simultaneous with your reading this entry, then it seems that Rome must be burning at the same time you are reading this entry. (This problem was advanced by Nelson Pike; Stump and Kretzmann have replied that the simultaneity involved in God's eternal knowledge is not transitive). A different problem arises with respect to eternity and omniscience. If God is outside of time, can God know what time it is now? Arguably, there is a fact of the matter that it is now, say, midnight on 1 July 2010. A God outside of time might know that at midnight on 1 July 2010 certain things occur, but could God know when it isnow that time? The problem is that the more emphasis we place on the claim that God's supreme existence is independent of time, the more we seem to jeopardize taking seriously time as we know it. Finally, while the great monotheistic traditions provide a portrait of the Divine as supremely different from the creation, there is also an insistence on God's proximity or immanence. For some theists, describing God as a person or person-like (God loves, acts, knows) is not to equivocate. But it is not clear that an eternal God could be personal. For recent work on God's relation to time, see work by Katherin Rogers (Rogers 2007, 2008).
4.1.3 The goodness of God
All known world religions address the nature of good and evil and commend ways of achieving human well-being, whether this be thought of in terms of salvation, liberation, deliverance, enlightenment, tranquility, or an egoless state of Nirvana. Notwithstanding important differences, there is a substantial overlap between many of these conceptions of the good as witnessed by the commending of the Golden Rule (“Do unto others as you would have them do unto you”) in many religions. Some religions construe the Divine as in some respect beyond our human notions of good and evil. In some forms of Hinduism, for example, Brahman has been extolled as possessing a sort of moral transcendence, and some Christian theologians and philosophers have likewise insisted that God is only a moral agent in a highly qualified sense, if at all (Davies 1993). To call God good is, for them, very different from calling a human being good.
Here I note only some of the ways in which philosophers have articulated what it means to call God good. In treating the matter, there has been a tendency either to explain God's goodness in terms of standards that are not God's creation and thus, in some measure, independent of God's will, or in terms of God's will and the standards God has created. The latter view has been termed theistic voluntarism. A common version of theistic voluntarism is the claim that for something to be good or right simply means that it is willed by God and for something to be evil or wrong means that it is forbidden by God.
Theistic voluntarists face several difficulties: moral language seems intelligible without having to be explained in terms of the Divine will. Indeed, many people make what they take to be objective moral judgments without making any reference to God. If they are using moral language intelligibly, how could it be that the very meaning of such moral language should be analyzed in terms of Divine volitions? New work in the philosophy of language may be of use to theistic voluntarists. According to a causal theory of reference, “water” necessarily designates H2O. It is not a contingent fact that water is H2O notwithstanding the fact that many people can use the term “water” without knowing its composition. Similarly, could it not be the case that “good” may refer to that which is willed by God even though many people are not aware of (or even deny) the existence of God? Another difficulty for voluntarism lies in accounting for the apparent meaningful content of claims like “God is good.” It appears that in calling God “good” the religious believer is saying more than “God wills what God wills.” If so, must not the very notion of goodness have some meaning independent of God's will? Also at issue is the worry that if voluntarism is accepted, the theist has threatened the normative objectivity of moral judgments. Could God make it the case that moral judgments were turned upside down? For example, could God make cruelty good? Arguably, the moral universe is not so malleable. In reply, some voluntarists have sought to understand the stability of the moral laws in light of God's immutably fixed, necessary nature.
By understanding God's goodness in terms of God's being (as opposed to God's will alone), we come close to the non-voluntarist stand. Aquinas and others hold that God is essentially good in virtue of God's very being. All such positions are non-voluntarist in so far as they do not claim that what it means for something to be good is that God wills it to be so. The goodness of God may be articulated in various ways, either by arguing that God's perfection requires God being good as an agent or by arguing that God's goodness can be articulated in terms of other Divine attributes such as those outlined above. For example, because knowledge is in itself good, omniscience is a supreme good. God has also been considered good in so far as God has created and conserves in existence a good cosmos. Debates over the problem of evil (if God is indeed omnipotent and perfectly good, why is there evil?) have poignancy precisely because they challenge this chief judgment over God's goodness. (The debate over the problem of evil is taken up in section 4.2.)
The choice between voluntarism and seeing God's very being as good is rarely strict. Some theists who oppose a full-scale voluntarism allow for partial voluntarist elements. According to one such moderate stance, while God cannot make cruelty good, God can make some actions morally required or morally forbidden which otherwise would be morally neutral. Arguments for this have been based on the thesis that the cosmos and all its contents are God's creation. According to some theories of property, an agent making something good gains entitlements over the property. The crucial moves in arguments that the cosmos and its contents belong to their Creator have been to guard against the idea that human parents would then “own” their children (they do not, because parents are not radical creators like God), and the idea that Divine ownership would permit anything, thus construing our duties owed to God as the duties of a slave to a master (a view to which not all theists have objected). Theories spelling out why and how the cosmos belongs to God have been prominent in all three monotheistic traditions. Plato defended the notion, as did Aquinas and Locke. (See Brody 1974 for a defense.)
A new development in theorizing about God's goodness has been advanced in Zagzebski 2004. Zagzebski contends that being an exemplary virtuous person consists in having good motives. Motives have an internal, affective or emotive structure. An emotion is “an affective perception of the world” (Zagzebski 2004, xvi) that “initiates and directs action” (Ibid., 1). The ultimate grounding of what makes human motives good is if they are in accord with the motives of God. Zagzebski's theory is perhaps the most ambitious virtue theory in print, offering an account of human virtues of God. Not all theists resonate with her bold claim that God is a person who has emotions, but many allow that (at least in some analogical sense) God may be see as personal and having affective states.
One other effort worth noting to link judgments of good and evil with judgments about God relies upon the ideal observer theory of ethics. According to this theory, moral judgments can be analyzed in terms of how an ideal observer would judge matters. To say an act is right entails a commitment to holding that if there were an ideal observer, it would approve of the act; to claim an act is wrong entails the thesis that if there were an ideal observer, it would disapprove of it. The theory can be found in works by Hume, Adam Smith, and Hare and Firth (1970). The ideal observer is variously described, but typically is thought of as an impartial omniscient regarding non-moral facts (facts that can be grasped without already knowing the moral status or implications of the fact—for instance, “He did something bad” is a moral fact; “He hit Smith” is not), and as omnipercipient (Firth's term for adopting a position of universal affective appreciation of the points of view of all involved parties). The theory receives some support from the fact that most moral disputes can be analyzed in terms of different parties challenging each other to be impartial, to get their empirical facts straight, and to be more sensitive—for example, by realizing what it feels like to be disadvantaged. The theory has formidable critics and defenders. If true, it does not follow that there is an ideal observer, but if it is true and moral judgments are coherent, then the idea of an ideal observer is coherent. Given certain conceptions of God in the three great monotheistic traditions, God fits the ideal observer description (and more besides, of course). Should an ideal observer theory be cogent, a theist would have some reason for claiming that atheists committed to normative, ethical judgments are also committed to the idea of a God or a God-like being. (For a defense of a theistic form of the ideal observer theory, see Taliaferro 2005; for criticism see Anderson, 2005.)