Knowledge and Christian Belief
Preface & Chapter 1 — Can We Speak and Think about God?
Plantinga introduces his project as a shorter, accessible version of Warranted Christian Belief, defending Christian belief’s rationality against New Atheist rhetoric (Dawkins, Dennett, Harris, Hitchens) that he finds long on vitriol but short on argument. The book’s central claims are: critiques of Christian belief’s rationality are inconclusive; such belief can constitute knowledge; and objections to it presuppose its falsehood. Chapter 1 addresses a preliminary challenge: some Kantian-inspired thinkers (e.g., Gordon Kaufman) argue God, as ultimate reality, lies beyond human concepts, rendering all God-talk meaningless. Kaufman reduces “God” to a symbol of cosmic activity rather than a transcendent person. Plantinga counters that this view is self-defeating — asserting we cannot think about God is itself a thought about God — and that no compelling reason blocks our conceptual grasp of God. He concludes Christian belief is a genuine phenomenon and proceeds to examine its rationality.
Chapter 2 — What Is the Question?
Plantinga distinguishes de facto objections (belief is false) from de jure objections (belief is irrational or unjustified), focusing on the latter. He dismisses the arrogance objection and targets classical foundationalism — Locke’s view that only self-evident or incorrigible beliefs are properly basic. Plantinga shows classical foundationalism is self-referentially incoherent and that beliefs aren’t voluntarily controlled, so duty-based justification fails. Turning to the strongest de jure challenges, he examines Marx (belief arises from social dysfunction causing cognitive malfunction) and Freud (belief arises from wish-fulfillment, aimed at comfort rather than truth). He reframes both as claims that theistic belief lacks warrant — the property distinguishing knowledge from mere true belief — and introduces his four-condition account: proper function, appropriate environment, aim at truth, and successful design.
Chapter 3 — Warranted Belief in God
Plantinga presents the Aquinas/Calvin (A/C) model: God has endowed humans with a sensus divinitatis — a natural cognitive faculty producing belief in God non-inferentially in response to experiences like cosmic grandeur, moral awareness, or mortal danger. Like perception or memory, these beliefs are properly basic with respect to warrant. However, sin can impair or suppress this faculty. Plantinga argues that the de jure question is not independent of the de facto question. If theism is true, a divinely designed truth-aimed faculty likely confers warrant; if false, no such faculty exists. This undercuts Freud’s critique, which tacitly presupposes atheism. Plantinga inverts Marx and Freud: unbelief, not belief, reflects cognitive malfunction — the sensus divinitatis suppressed by sin. Therefore, no independent de jure objection to theistic belief succeeds.
Chapter 4 — The Extended A/C Model
Plantinga extends the A/C model from mere theism to full-blooded Christian belief, arguing that belief in sin, atonement, and salvation can be justified, rational, and warranted — even for educated twenty-first-century people. He contends that sin is both a cognitive and affective disorder: it damages the sensus divinitatis and skews our loves toward self-aggrandizement, using examples like academic envy and pride as “aboriginal sin.” Salvation operates through a three-tiered cognitive process: Scripture (divinely inspired testimony), the Holy Spirit’s internal witness, and faith. Because the Holy Spirit’s work is a properly functioning, truth-aimed belief-producing process designed by God, Christian belief satisfies all warrant conditions. Plantinga also dismisses the charge of “fundamentalism” as mere indexical name-calling lacking substantive philosophical argument.
Chapter 5 — Faith
Plantinga rejects Dawkins’s characterization of faith as “belief despite lack of evidence,” defining it — following Calvin and the Heidelberg Catechism — as “a firm and certain knowledge of God’s benevolence towards us.” Faith is a cognitive state produced by the Holy Spirit’s internal instigation working with Scripture as divine testimony. It meets all four warrant conditions: proper function, appropriate environment, truth-aimed design, and reliable production of true beliefs. Crucially, faith is properly basic — it doesn’t require argument or historical evidence — and is no “leap in the dark,” but rather resembles the compelling phenomenology of memory or arithmetic. Plantinga concedes, citing Calvin, that typical faith mixes certainty with doubt, so full warrant sufficient for knowledge may obtain only in paradigmatic cases, not necessarily in every instance.
Chapter 6 — Sealed Upon Our Hearts
This chapter explores the affective dimension of faith that distinguishes believers from demons, who “believe and shudder.” Faith involves right affections — love, gratitude, trust — produced by the Holy Spirit. Drawing on Calvin (whose emblem was a flaming heart), Edwards (true religion consists in holy affections), and Luther (faith in God, not merely concerning God), Plantinga argues that conversion fundamentally heals disordered affections. He develops the concept of eros as longing for union with God, citing the Psalms’ yearning language and everyday experiences of beauty that trigger inexplicable desire. Against the tradition of divine impassibility, Plantinga argues that God’s love includes eros — not merely agape — as seen in Trinitarian love between Father and Son, and in scriptural imagery of bridegroom and bride.
Chapter 7 — Objections
Plantinga defends the extended A/C model against two objections from J.L. Mackie concerning whether religious experience can warrant Christian belief. First, against Mackie’s assumption that theistic belief functions like a scientific hypothesis requiring argumentative support from experience, Plantinga counters that on the A/C model, the sensus divinitatisand the Holy Spirit’s internal instigation produce belief directly as occasions, not as premises — just as perception and memory yield warranted beliefs without inferential backing. Second, against Mackie’s claim that religious experience cannot reveal specific divine attributes because such experience is logically compatible with God’s nonexistence, Plantinga argues by analogy: seeing a horse is compatible with no horse being present, yet one still knows by experience that a horse is there. Doxastic experience — the sense that a proposition “seems right” — confers warrant without requiring entailment, so religious belief can constitute knowledge even without deductive certainty.
Chapter 8 — Defeaters? Historical Biblical Criticism
Plantinga argues that historical biblical criticism (HBC) does not constitute a defeater for Christian belief held in the basic way. He distinguishes Troeltschian HBC — which implicitly presupposes naturalism, assuming miracles never occur and God never acts specially in the world — from Duhemian HBC, which limits itself to premises all parties accept and yields only meager results (illustrated by John Meier’s Marginal Jew project). Since the Christian possesses additional epistemic resources — Scripture, the internal instigation of the Holy Spirit, faith — the fact that Duhemian scholarship cannot confirm distinctive Christian claims is no defeater. It merely reflects self-imposed methodological constraints that exclude evidence the believer legitimately possesses, like mowing a lawn with nail scissors.
Chapter 9 — Defeaters? Pluralism
Plantinga examines whether religious pluralism — the existence of diverse, incompatible religious beliefs held by intelligent people — constitutes a defeater for Christian exclusivism. He addresses both a moral charge (that exclusivism is arrogant) and an epistemic charge (that it is arbitrary). Against the moral charge, he argues that holding a belief one knows others reject need not display egoism, analogizing to Quakers who opposed slavery without arguments convincing their contemporaries. Against the epistemic charge, he contends the believer need not consider herself on an epistemic par with dissenters if she reasonably believes she possesses special warrant-producing sources — the sensus divinitatis and the internal instigation of the Holy Spirit — that dissenters lack. Pluralism may reduce some believers’ confidence, but it can also occasion deeper reflection that strengthens belief. Therefore, the facts of pluralism need not constitute a defeater for Christian belief.
Chapter 10 — Defeaters? Evil
Plantinga confronts the problem of evil as the most formidable candidate defeater for theistic belief. He distinguishes the spiritual/pastoral problem — believers’ anguish and resentment toward God — from the epistemological question of whether evil defeats warranted Christian belief. After dismissing the logical incompatibility argument as widely refuted, he critiques probabilistic/evidential arguments, noting that beliefs can rationally override contrary evidence when grounded in independent warrant sources like perception. He identifies the strongest atheological case as a non-argumentative “inverse sensus divinitatis” — the intuitive sense that no good God could permit such horrors. He counters that for fully rational persons with properly functioning cognition, God’s presence remains evident; for fallen believers, the sensus divinitatis is progressively repaired through faith and regeneration, and knowledge of Christ’s redemptive suffering restores confidence. Using Guido de Bres’s imprisonment letter as illustration, Plantinga concludes that evil provides no defeater for theistic belief.