Editing Alvin Plantinga (section)

=== Reformed epistemology ===
{{Main|Reformed epistemology}}
What Plantinga calls "Reformed epistemology" holds that belief in God can be rational and justified even without arguments or evidence for the existence of God. More specifically, he argues belief in God is [[properly basic]], and due to a religious [[Internalism and externalism|externalist]] epistemology, he claims that it could be justified independently of evidence.  His externalist epistemology, called "proper functionalism", is a form of [[epistemological]] [[reliabilism]].

Plantinga discusses his view of Reformed epistemology and proper functionalism in a three-volume series. In the first book of the trilogy, ''[[Warrant: The Current Debate]]'', Plantinga introduces, analyzes, and criticizes 20th-century developments in analytic epistemology, particularly the works of [[Roderick Chisholm|Chisholm]], [[Laurence BonJour|BonJour]], [[William Alston|Alston]], [[Alvin Goldman|Goldman]], and others.<ref>Alvin Plantinga, ''Warrant: The Current Debate'', New York: Oxford University Press, 1993.</ref> In the book, Plantinga argues specifically that the theories of what he calls "warrant"—what many others have called [[Theory of justification|justification]] (Plantinga draws out a difference: justification is a property of a person holding a belief while warrant is a property of a belief)—put forth by these epistemologists have systematically failed to capture in full what is required for knowledge.<ref>Plantinga, ''Warrant: The Current Debate'', 1993. 3.</ref>

In the second book, ''[[Warrant and Proper Function]]'', he introduces the notion of warrant as an alternative to justification and discusses topics like self-knowledge, memories, perception, and probability.<ref>Alvin Plantinga, ''Warrant and Proper Function'', New York: Oxford University Press, 1993.</ref> Plantinga's "proper function" account argues that as a necessary condition of having warrant, one's "belief-forming and belief-maintaining apparatus of powers" are functioning properly—"working the way it ought to work".<ref>WPF, p. 4</ref> Plantinga explains his argument for proper function with reference to a "design plan", as well as an environment in which one's cognitive equipment is optimal for use. Plantinga asserts that the design plan does not require a designer: "it is perhaps possible that evolution (undirected by God or anyone else) has somehow furnished us with our design plans",<ref>WPF, p. 21</ref> but the paradigm case of a design plan is like a technological product designed by a human being (like a radio or a wheel). Ultimately, Plantinga argues that epistemological [[Naturalism (philosophy)|naturalism]]—i.e. [[epistemology]] that holds that warrant is dependent on natural faculties—is best supported by supernaturalist metaphysics—in this case, the belief in a [[creator God]] or designer who has laid out a design plan that includes cognitive faculties conducive to attaining knowledge.<ref>WPF, 237.</ref>

According to Plantinga, a belief, B, is warranted if:

<blockquote>(1) the cognitive faculties involved in the production of B are functioning properly...; (2) your cognitive environment is sufficiently similar to the one for which your cognitive faculties are designed; (3) ... the design plan governing the production of the belief in question involves, as purpose or function, the production of true beliefs...; and (4) the design plan is a good one: that is, there is a high statistical or objective probability that a belief produced in accordance with the relevant segment of the design plan in that sort of environment is true.<ref>Plantinga, ''Warrant and Proper Function'', 1993. 194.</ref></blockquote>

Plantinga seeks to defend this view of proper function against alternative views of proper function proposed by other philosophers which he groups together as "naturalistic", including the "functional generalization" view of [[John L. Pollock|John Pollock]], the evolutionary/etiological account provided by [[Ruth Millikan]], and a dispositional view held by [[John Bigelow]] and Robert Pargetter.<ref>WPF, p. 199-211.</ref> Plantinga also discusses his [[#Evolutionary argument against naturalism|evolutionary argument against naturalism]] in the later chapters of ''Warrant and Proper Function''.<ref>{{Cite journal |last=Fales |first=E. |year=1996 |title=Plantinga's Case against Naturalistic Epistemology |journal=Philosophy of Science |volume=63 |issue=3 |pages=432–451 |doi=10.1086/289920|s2cid=170510977 }}</ref>

In 2000, the third book of the trilogy, ''Warranted Christian Belief'', was published. In this volume, Plantinga's warrant theory is the basis for his theological end: providing a philosophical basis for Christian belief, an argument for why Christian theistic belief can enjoy warrant. In the book, he develops two models for such beliefs, the "A/C" ([[Thomas Aquinas|Aquinas]]/[[John Calvin|Calvin]]) model, and the "Extended A/C" model. The former attempts to show that a belief in God can be justified, warranted and rational, while the Extended model tries to show that specifically Christian theological beliefs including the [[Trinity]], the [[Incarnation (Christianity)|Incarnation]], the [[Resurrection of Jesus|resurrection of Christ]], the [[Atonement in Christianity|atonement]], [[Salvation in Christianity|salvation]]. etc. Under this model, Christians are justified in their beliefs because of the work of the [[Holy Spirit in Christianity|Holy Spirit]] in bringing those beliefs about in the believer.

James Beilby has argued that the purpose of Plantinga's ''Warrant'' trilogy, and specifically of his ''Warranted Christian Belief'', is firstly to make a form of argument against religion impossible—namely, the argument that whether or not Christianity is true, it is irrational—so "the skeptic would have to shoulder the formidable task of demonstrating the falsity of Christian belief"<ref>{{Cite book |title=Alvin Plantinga |last=Beilby |first=James |date=2007 |publisher=Cambridge University Press |isbn=978-0-521-67143-9 |editor-last=Baker |editor-first=Deane-Peter |location=Cambridge |pages=125–165 |chapter=Plantinga's Model of Warranted Christian Belief}}</ref> rather than simply dismiss it as irrational. In addition, Plantinga is attempting to provide a philosophical explanation of how Christians should think about their own Christian belief.