Faith and Reason

The relationship between faith and reason is one of the oldest and most fundamental questions in the philosophy of religion. Can belief in God be rationally justified, or does genuine faith require a leap beyond — or even against — reason? This lesson examines the major positions on the faith-reason relationship, from Aquinas's confidence in natural theology to Kierkegaard's passionate leap, and from Plantinga's reformed epistemology to the radical fideism of Wittgensteinian philosophy of religion.

Aquinas and the Harmony of Faith and Reason

Natural Theology

St Thomas Aquinas (1225–1274) represents the classical position that faith and reason are complementary, not contradictory. In the Summa Theologica and Summa Contra Gentiles, Aquinas argued that human reason, operating independently of revelation, can establish certain truths about God — including God's existence, God's unity, and some of God's attributes (power, wisdom, goodness). This enterprise is known as natural theology.

Key Definition: Natural Theology — The attempt to establish truths about God through human reason and observation of the natural world, without reliance on special revelation (Scripture, prophecy, religious experience).

Aquinas's Five Ways — the arguments from motion, causation, contingency, degrees of perfection, and teleology — are the most famous examples of natural theology. Each begins with an observable feature of the world and reasons to God as its ultimate explanation. For Aquinas, these arguments are genuinely demonstrative — they provide certain knowledge of God's existence, accessible to any rational person regardless of their religious background.

The Preambles and Articles of Faith

Aquinas distinguished between two categories of religious truth:

Category	Description	Examples
Preambles of faith (praeambula fidei)	Truths about God that can be known by reason alone	God's existence, God's unity, God's incorporeality
Articles of faith (articuli fidei)	Truths about God that exceed reason and can only be known through revelation	The Trinity, the Incarnation, the Resurrection

The preambles of faith are accessible to reason; the articles of faith require divine revelation. Crucially, Aquinas insisted that the two can never contradict each other, since both reason and revelation have their source in God — the author of all truth. If a philosophical conclusion appears to contradict revealed truth, there must be an error in the reasoning, not a genuine conflict between faith and reason.

Grace Perfects Nature

Aquinas's famous axiom — gratia non tollit naturam sed perficit ("grace does not destroy nature but perfects it") — expresses his conviction that the supernatural builds upon and elevates the natural. Reason provides the foundation; faith completes the structure. The philosopher can know that God exists; the believer, through revelation, can know who God is.

Kierkegaard and the Leap of Faith

The Limits of Rational Theology

Soren Kierkegaard (1813–1855), the Danish philosopher often regarded as the father of existentialism, mounted a radical challenge to Aquinas's confidence in natural theology. Kierkegaard argued that the attempt to prove God's existence through rational argument fundamentally misunderstands the nature of faith. Faith is not the conclusion of a syllogism — it is a passionate, personal commitment that involves risk, uncertainty, and existential engagement.

In Concluding Unscientific Postscript (1846), Kierkegaard wrote: "If I am able to apprehend God objectively, I do not have faith; but because I cannot do this, I must have faith." For Kierkegaard, the objective uncertainty of God's existence is not an obstacle to faith but its very condition. If God's existence could be demonstrated with mathematical certainty, faith would be unnecessary — and its distinctive value would be lost.

Key Definition: Leap of Faith — Kierkegaard's concept that genuine faith requires a passionate, personal commitment that goes beyond what reason can justify. It involves embracing objective uncertainty with subjective intensity.

Objective Uncertainty and Subjective Passion

Kierkegaard distinguished sharply between objective and subjective truth. Objective truth concerns what is said — whether a proposition corresponds to reality. Subjective truth concerns how it is said — the manner in which a person relates to a belief. For Kierkegaard, religious truth is fundamentally subjective: "The objective uncertainty, held fast through appropriation with the most passionate inwardness, is the truth, the highest truth there is for an existing person."

A person who clings passionately to God in the face of uncertainty has a deeper relationship with truth than someone who accepts God's existence as a detached intellectual conclusion. The risk inherent in faith is what gives it its value.

The Three Stages of Existence

Kierkegaard described three stages or spheres of human existence:

Stage	Characteristics	Limitations
Aesthetic	Pursuit of pleasure, novelty, and immediate experience	Leads to boredom, despair, and the absence of meaning
Ethical	Commitment to duty, moral responsibility, and universal principles	Cannot resolve the deepest existential questions; may lead to self-righteousness
Religious	A personal, passionate relationship with God through faith	Requires the leap of faith — a radical commitment that transcends reason

The transition between stages cannot be achieved through rational deliberation — it requires a qualitative leap, a moment of existential decision that transforms the individual's entire mode of being.

The Paradox of the Incarnation

Kierkegaard argued that the central claim of Christianity — that the eternal, infinite God became a finite, temporal human being in Jesus Christ — is an absolute paradox that reason cannot comprehend. The Incarnation is not merely difficult to understand; it is a logical contradiction that offends reason. Yet this is precisely why it demands faith rather than rational assent. "The absurd is precisely by its objective repulsion the measure of the intensity of faith in inwardness" (Concluding Unscientific Postscript).

Reformed Epistemology: Alvin Plantinga

The Challenge to Classical Foundationalism

Alvin Plantinga (b. 1932) developed reformed epistemology — a philosophical position that challenges the assumption that belief in God requires evidence or argument to be rational. Plantinga's target is classical foundationalism — the epistemological view that a belief is rational only if it is either self-evident, evident to the senses, or supported by evidence from beliefs that are self-evident or evident to the senses.

Plantinga argues that classical foundationalism is self-refuting: the claim "a belief is rational only if it is self-evident, evident to the senses, or based on such evidence" is itself neither self-evident nor evident to the senses. By its own criteria, classical foundationalism is irrational.

Key Definition: Reformed Epistemology — The view, associated with Alvin Plantinga, that belief in God can be rational without being based on evidence or argument. Belief in God can be "properly basic" — a foundational belief that does not require support from other beliefs.

Belief in God as Properly Basic

Plantinga contends that belief in God can be properly basic — a foundational belief that is rational without needing to be based on argument or evidence from other beliefs. Just as we accept beliefs about the external world ("I see a tree"), memory ("I had breakfast this morning"), and other minds ("that person is in pain") without demanding proof, so too belief in God can be accepted as a basic belief, grounded in certain experiences.

What kinds of experiences ground basic belief in God? Plantinga suggests experiences such as:

A sense of God's presence in nature — "God made all this"
A sense of divine disapproval when doing wrong — "God is displeased with me"
A sense of gratitude directed towards God — "thank God for this"
Reading Scripture and feeling that God is speaking

These experiences function as the "grounds" for basic belief in God, just as sensory experiences ground perceptual beliefs. Belief in God is not arbitrary or groundless — it arises naturally in response to certain experiential triggers.

The Sensus Divinitatis

Drawing on John Calvin (1509–1564), Plantinga posits a sensus divinitatis — a natural, innate cognitive faculty that produces belief in God when triggered by appropriate circumstances (the beauty of nature, awareness of moral obligation, the sense of divine presence). The sensus divinitatis is analogous to perception: just as our eyes produce beliefs about the physical world, the sensus divinitatis produces beliefs about God. Sin has damaged but not destroyed this faculty, which is why not everyone believes in God.

Fideism

What Is Fideism?

Fideism is the view that faith is independent of — and may even be contrary to — reason. The fideist holds that religious belief does not need rational justification and cannot be established or undermined by philosophical argument. Faith is its own source of authority.

Historical fideists include:

Thinker	Position
Tertullian (c. 155–240)	Famously asked, "What has Athens to do with Jerusalem?" — implying that philosophy (Athens) has nothing to contribute to theology (Jerusalem). Often attributed the phrase credo quia absurdum ("I believe because it is absurd"), though this is a paraphrase.
Blaise Pascal (1623–1662)	Argued that "the heart has its reasons that reason does not know." Pascal's Wager proposes that it is pragmatically rational to believe in God even without evidence — the potential gains (eternal salvation) outweigh the potential losses.
Martin Luther (1483–1546)	Called reason "the Devil's greatest whore" — a tool that leads people away from faith when applied to theological questions.

Criticisms of Fideism

Fideism cannot distinguish between rival faith claims — if faith requires no rational justification, any belief system is equally valid
It abandons the possibility of meaningful dialogue between faith traditions
It may encourage intellectual irresponsibility — believing without evidence

Wittgensteinian Fideism

Language Games and Forms of Life

Ludwig Wittgenstein (1889–1951) developed the concept of language games — different modes of discourse, each with its own rules, standards, and criteria of meaning. Scientific language, moral language, aesthetic language, and religious language are different language games, each governed by its own internal logic. A statement that is meaningful within one language game may be meaningless or misapplied in another.

D.Z. Phillips (1934–2006) applied Wittgenstein's insights to religion, developing what is sometimes called Wittgensteinian fideism (though Phillips rejected the label). Phillips argued that religious language constitutes its own unique language game. When believers say "God exists," they are not making an empirical claim that can be tested by scientific methods — they are expressing a commitment, a way of seeing the world, a framework of meaning.

Key Definition: Language Game — Wittgenstein's concept that language functions in multiple distinct ways, each with its own rules and criteria of meaning. Religious language is a distinct language game that cannot be judged by the criteria of science or ordinary empirical discourse.

Implications

If religious language is a self-contained language game, then:

It cannot be refuted by scientific evidence (science and religion are different games)
It cannot be supported by philosophical arguments (arguments for God's existence misunderstand the nature of religious belief)
The verification principle cannot declare religious language meaningless (the principle belongs to a different language game)
Religious belief is a practice embedded in a form of life — a communal, lived reality that gives religious language its meaning

Criticisms of Wittgensteinian Fideism

Isolates religion from criticism — if religion is a self-contained language game, it becomes immune to external critique, which seems intellectually irresponsible
Conflates belief with practice — Phillips seems to reduce religious belief to a way of living, stripping it of its cognitive content. Most believers think "God exists" is a factual claim, not merely a way of expressing a commitment
The problem of inter-game communication — in practice, scientific and religious claims do interact and sometimes conflict (e.g., creation vs evolution). The strict separation of language games may be artificial

Evaluation

Strengths

Aquinas provides a robust framework for integrating faith and reason, showing that they need not be in conflict
Kierkegaard captures something important about the existential, personal nature of faith — reducing faith to intellectual assent misses its transformative character
Plantinga offers a sophisticated defence of the rationality of theistic belief without requiring traditional arguments for God's existence
Wittgenstein/Phillips draws attention to the distinctive logic of religious language and the danger of treating it as failed science

Limitations

Aquinas may overestimate what reason can prove — the Five Ways have been extensively criticised, and many philosophers remain unconvinced
Kierkegaard risks making faith irrational — if faith requires embracing the absurd, how does it differ from wishful thinking or delusion?
Plantinga's sensus divinitatis is difficult to verify — critics argue it is an ad hoc postulate designed to protect theistic belief from criticism
Wittgensteinian fideism may trivialise religious belief by denying that it makes genuine truth claims about reality

Exam Tip: The faith-reason debate is central to AQA A-Level Religious Studies. The strongest answers will demonstrate precise knowledge of Aquinas's distinction between preambles and articles of faith, Kierkegaard's concept of subjective truth, Plantinga's reformed epistemology, and the Wittgensteinian approach. Always evaluate — consider which position best accounts for the nature of religious belief and whether faith without rational grounding is intellectually responsible or genuinely liberating.