Plantinga, Alvin (1932–)
Born in Ann Arbor, Michigan, Alvin Plantinga is one of the most important and influential philosophers of the twentieth and early twenty-first centuries. His publications range over a wide variety of fields, but his most enduring contributions have been in metaphysics, epistemology, and, especially, the philosophy of religion. He is best known for his work on the metaphysics of necessity and possibility, for his defense of the view that knowledge is to be analyzed partly in terms of proper function, for his development of the "free will defense" against the so-called "logical problem of evil," for his many and vigorous defenses of the rationality of religious belief, and for his much-discussed "evolutionary argument against naturalism."
Plantinga earned his BA in philosophy and psychology from Calvin College in 1953, and he cites his experience at Calvin as perhaps the single most significant intellectual influence in his life. There he studied with Henry Stob and Harry Jellema, the latter of whom played an especially formative role in his intellectual development. Plantinga received his MA in philosophy from the University of Michigan in 1955, and his PhD from Yale in 1958 under the supervision of Paul Weiss. He was elected to the American Academy of Arts and Sciences in 1975, co-founded the Society of Christian Philosophers in 1978, served as President of the Central Division of the American Philosophical Association in 1981 and 1982, and served as President of the Society of Christian Philosophers from 1983 to 1986. He has given the prestigious Gifford Lectures twice, and in a 1980 article he was heralded by Time magazine as "America's leading orthodox Protestant philosopher of God."
Plantinga's most influential work in metaphysics has focused primarily on the metaphysics of modality. In The Nature of Necessity (1974), as well as in various papers, a central theme is the exposition and defense of a realist and actualist construal of possible worlds and modal properties. On his view, the standard possible worlds semantics for modal logic is to be taken with metaphysical seriousness: it is not a mere heuristic device; possible worlds are not merely useful fictions. Rather, possible worlds exist. They are abstract states of affairs of a certain kind—something like total or complete ways that a world history might have gone. Moreover, individual things have modal properties —properties such as being possibly seven feet tall, or being necessarily even —and, Plantinga thinks, realism about such properties requires one to believe that individual things exist in other worlds. On his view, a thing exists in another possible world only if, had that world been actual, the thing itself, not a mere stand-in or counterpart, would have existed. Thus, if Fred has the property being possibly seven feet tall, then there is a possible world such that, had that world been actual, Fred himself would have existed and would have been seven feet tall. Ultimately, this understanding of modal properties, together with his commitment to strong form of actualism, leads Plantinga to endorse the controversial view that objects have individual essences —properties that are both essential and essentially unique to them.
Plantinga's major works in epistemology are the volumes that comprise his Warrant trilogy (1993a, 1993b, 2000). Warrant, according to Plantinga, is that property or quantity that distinguishes knowledge from mere true belief. The main goals of the Warrant books are to identify the necessary and sufficient conditions for warrant, and to defend an affirmative answer to the question whether distinctively Christian belief can be warranted.
In the first volume of the trilogy, Plantinga surveys a broad range of post-Gettier analyses of knowledge, arguing that all of them founder on counterexamples involving cognitive malfunction. The basic problem is that, for each candidate analysis of "S knows that p," the conditions listed as necessary and sufficient for knowledge could be satisfied by a person whose cognitive faculties are malfunctioning in such a way that, intuitively, beliefs produced by faculties behaving in that way fail to count as knowledge. He also argues for the striking and controversial conclusion that justification, construed at least in part as a matter of epistemic duty-fulfillment, is not necessary for knowledge at all.
In the second volume, Plantinga articulates and defends a new analysis of knowledge, according to which (roughly) S knows that p if and only if S believes that p, p is true, and S's belief that p is the product of faculties that are properly functioning, successfully aimed at truth, and operating in an appropriate environment. The notions of proper function and appropriate environment are normative notions; but, Plantinga says, the normativity involved is of a sort commonly invoked in the natural sciences. Thus, Plantinga regards his analysis as, strictly speaking, an instance of "epistemology naturalized." But he also argues that his brand of epistemology naturalized flourishes best in the context of a supernaturalistic metaphysics. Toward establishing this conclusion, he begins by arguing that proper function is an irreducibly normative notion that does not admit of a purely naturalistic analysis. He then attacks naturalism directly, arguing that belief in naturalism and evolutionary theory together is epistemically self-defeating and therefore irrational. This latter argument is the so-called "evolutionary argument against naturalism."
The third volume of the Warrant trilogy applies the account of knowledge defended in the second volume in the service of an argument for the possibility of warranted Christian belief. The central and striking thesis of the book is that if Christian belief is true, then it is warranted. This conclusion is important because it implies, contrary to widespread opinion, that objections against the rationality of Christian belief are not independent of objections against the truth of Christian belief. In order to defend the conclusion that Christian belief is unwarranted, one must first defend the conclusion that it is false. In support of his central thesis, Plantinga begins by arguing that the only really philosophically interesting question about the rationality of Christian belief is the question that asks whether Christian belief is or can be warranted. He then notes that, in light of the analysis of knowledge proposed in the second volume, Christian belief can be warranted so long as it is produced by properly functioning faculties that are successfully aimed at truth and functioning in a suitable environment. Much of the rest of the volume, then, is devoted to establishing the conclusion that if Christian belief is true, then these conditions are satisfied.
Philosophy of Religion
Plantinga's work in the philosophy of religion has focused on what is sometimes referred to as "negative apologetics": the task of showing that objections to religious belief are unsuccessful. Thus, to take just a few examples, Plantinga has argued that the proposition that God exists is logically consistent with the proposition that evil exists; that the existence of evil does not constitute a defeater for the rationality of Christian belief; that widespread religious pluralism and intractable disagreement on religious matters do not provide reason to doubt that one knows that one's own religious beliefs are true; and that what he takes to be the correct views about human freedom and moral responsibility are not in tension with the traditional belief that God has perfect knowledge of the future.
Plantinga's focus on negative apologetics stems in part from his view that the warrant for Christian belief need not, and, in the ordinary case, does not come from philosophical argument but rather from something like religious experience. This view is a central theme in his work on religious epistemology, especially in the third volume of his Warrant trilogy (discussed above), but also in two earlier works: God and Other Minds (1967), and "Reason and Belief in God." Nevertheless, he does make occasional forays into the territory of positive apologetics. For example, in The Nature of Necessity and God, Freedom and Evil (1977), Plantinga argues that a modal version of the ontological argument for God's existence is both valid and plausibly sound. Likewise, Plantinga has devoted considerable energy to rebutting naturalism and its common companion, materialism.
Besides introducing important arguments into the literature on the philosophy of religion, however, Plantinga has also played an important role in shaping the way in which many religious philosophers now approach topics in their own fields of specialization. In his highly influential paper, "Advice to Christian Philosophers," (1984) Plantinga urges philosophers who share his Christian worldview to allow the presuppositions of that worldview to inform their work not only on topics in the philosophy of religion but elsewhere as well. He advises them not to become swept up in projects that arise out of and embody presuppositions of rival worldviews (such as naturalism or creative anti-realism), but to pursue a philosophical agenda in which one explores how a person with a Christian perspective ought to think about the various topics central to her discipline. This advice, itself an apt expression of one of the distinctive features of Plantinga's own work, has had a significant impact on the sorts of philosophical projects that have been undertaken in the late twentieth and early twenty-first centuries.
God and Other Minds. Ithaca, NY: Cornell University Press, 1967.
The Nature of Necessity. New York: Clarendon Press, 1974.
God, Freedom, and Evil. Grand Rapids, MI: Eerdmans, 1977.
"Reason and Belief in God." In Faith and Rationality, edited by Alvin Plantinga and Nicholas Wolterstorff, 16–93. Notre Dame: University of Notre Dame Press. 1983.
Warrant and Proper Function. New York: Oxford University Press, 1993b.
"Advice to Christian Philosophers," Faith and Philosophy 1: 253 – 71. Reprinted in Sennett, 1998.
The Analytic Theist: An Alvin Plantinga Reader. Edited by James F. Sennett. Grand Rapids, MI: Eerdmans, 1998.
Warranted Christian Belief. New York: Oxford University Press, 2000.
Essays in the Metaphysics of Modality, edited by Matthew Davidson. New York: Oxford University Press, 2003.
Tomberlin, James, and Peter van Inwagen, eds. Alvin Plantinga. Dordrecht, Netherlands: D. Reidel, 1985.
Michael C. Rea (2005)