Reformed epistemology

[2] Central to Reformed epistemology is the proposition that belief in God may be "properly basic" and not need to be inferred from other truths to be rationally warranted.

This point is answered by many theistic arguments which purport to provide sufficient propositional and physical evidence to warrant that belief, apart from reformed epistemology.

[13] 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, Laurence BonJour, William Alston, and Alvin Goldman.

[14] Plantinga argues that the theories of what he calls "warrant"—what many others have called justification (Plantinga draws out a difference: justification is a matter of fulfilling one's epistemic duties, whereas warrant is what transforms true belief into knowledge)—put forth by these epistemologists have failed to capture in full what is required for knowledge.

[17] 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.

Ultimately, Plantinga argues that epistemological 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 in some designer who has laid out a design plan that includes cognitive faculties conducive to attaining knowledge.

[21] Plantinga also discusses his evolutionary argument against naturalism in the later chapters of Warrant and Proper Function.

The former attempts to show that a belief in God can be justified, warranted and rational, while the Extended model tries to show that core Christian theological beliefs, including the Trinity, the Incarnation, the resurrection of Christ, the atonement, salvation, etc.

He is especially critical of New Atheism owing to their reliance on de jure objections to the Christian faith.

Suppose I believe that if I flap my arms with sufficient vigor, I can take off and fly about the room; could I defend myself against the charge of irrationality by claiming this belief is basic?

(p. 74)Plantinga's answer to this line of thinking is that the objection simply assumes that the criteria for "proper basicality" propounded by classical foundationalism (self-evidence, incorrigibility, and sense-perception) are the only possible criteria for properly basic beliefs.

[6] Other common criticisms of Plantinga's Reformed epistemology are that belief in God – like other sorts of widely debated and high-stakes beliefs – is "evidence-essential" rather than properly basic;[25] that plausible naturalistic explanations can be given for humans' supposedly "natural" knowledge of God;[26] and that it is arbitrary and arrogant for Christians to claim that their faith-beliefs are warranted and true (because vouched for by the Holy Spirit) while denying the validity of non-Christians' religious experiences.