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Intro to Philosophy Unit 6: Philosophy of Religion

Philosophy of religion examines arguments for and against God's existence and whether religious belief can be rational. This unit presents the classic arguments, the main objections and the debate over faith and evidence, as each side argues them.

Covers: Ontological arguments, Cosmological arguments, Design and fine-tuning arguments, The logical problem of evil, The evidential problem of evil and theodicies, Faith, reason and the ethics of belief, Pascal's Wager and religious epistemology

Study guide

Arguments for God's existence fall into families. Ontological arguments reason from the concept of God alone. Anselm defined God as 'that than which nothing greater can be conceived' and argued that such a being must exist in reality, since a being that existed only in the mind would be less great than one that exists in fact. Gaunilo replied with a parody about a perfect island, and Kant argued that existence is not a real predicate: it adds nothing to a concept. Alvin Plantinga later offered a modal version, arguing that if a maximally great being is even possible, it exists; critics say the possibility premise is the whole issue.

Cosmological arguments start from the existence of the world. Aquinas's Five Ways include arguments from motion, causation and contingency, each concluding that a regress of causes must end in a first cause or necessary being. Leibniz appealed to the principle of sufficient reason: everything has an explanation, and contingent things together require a necessary being. The kalam argument, revived by William Lane Craig, says whatever begins to exist has a cause and the universe began to exist. Teleological arguments start from order. William Paley compared nature to a watch implying a watchmaker. Hume questioned the analogy and what it could prove, Darwin offered natural selection as an alternative explanation, and modern defenders appeal to the fine-tuning of physical constants, which critics answer with the anthropic principle or a multiverse.

The most discussed argument against God is the problem of evil. J. L. Mackie argued that an all-powerful, all-knowing, perfectly good God is logically inconsistent with evil. Plantinga's free will defense replies that a world with free creatures who sometimes do wrong may be better than a world without freedom, and God cannot make free creatures always choose rightly. William Rowe's evidential version argues that intense suffering with no apparent purpose, like a fawn burned in a forest fire, makes God's existence improbable. Theodicies try to give God's reasons: Augustine traces evil to the misuse of free will, while John Hick sees the world as a place of soul-making. Skeptical theists argue that our failure to see a reason does not show there is none.

A further question is whether belief in God must rest on evidence. W. K. Clifford argued that it is always wrong to believe on insufficient evidence. William James replied that when an option is live, forced and momentous and evidence cannot decide it, our passional nature may decide. Pascal's Wager argues that belief is the rational bet, since its possible reward is infinite and its cost small; critics raise the many-gods objection and question whether belief can be chosen. Reformed epistemologists such as Plantinga argue that belief in God can be properly basic, rational without argument in the way belief in other minds is, while critics worry this lets almost any belief count as basic.

Key ideas

• Ontological arguments reason from the concept of God; Gaunilo and Kant offer the classic objections.
• Cosmological arguments reason from causation, change or contingency to a first cause or necessary being.
• Design arguments reason from order or fine-tuning; Hume, Darwin and the anthropic principle supply objections.
• The logical problem of evil alleges a contradiction; the free will defense aims to show consistency.
• The evidential problem argues that apparently pointless suffering makes God's existence improbable.
• Theodicies like Augustine's and Hick's try to give actual reasons why God would permit evil.
• Clifford's evidentialism, James's will to believe, Pascal's Wager and Reformed epistemology take different views of faith and evidence.

Formulas and rules

Common mistakes

• Mixing up cosmological arguments (from existence or causes) with teleological ones (from order or design).
• Treating the free will defense as if it claimed to explain every particular evil, rather than showing consistency.
• Confusing the logical problem of evil (contradiction) with the evidential problem (improbability).
• Assuming the kalam argument says everything has a cause, when it says whatever begins to exist does.
• Presenting Pascal's Wager as a proof of God's existence rather than a practical reason to believe.

Before the test, make sure you can

• Reconstruct Anselm's ontological argument and explain Gaunilo's and Kant's objections.
• Explain the cosmological arguments of Aquinas, Leibniz and the kalam tradition.
• Describe Paley's design argument and the objections from Hume, Darwin and the anthropic principle.
• Distinguish the logical and evidential problems of evil.
• Explain the free will defense, soul-making theodicy and skeptical theism.
• Compare Clifford's evidentialism with James's will to believe.
• Evaluate Pascal's Wager and state the many-gods objection.

Words to know

Ontological argument

An argument that God exists based on the concept of God, first given by Anselm.

Gaunilo's island

A parody of Anselm's argument claiming it would also prove a perfect island exists.

Existence is not a predicate

Kant's objection that existing adds nothing to a thing's concept.

Cosmological argument

An argument from the existence of the universe or causation to a first cause or necessary being.

Five Ways

Aquinas's five arguments for God, including those from motion, causation and contingency.

Principle of sufficient reason

Leibniz's principle that everything has an explanation for why it exists.

Kalam argument

The argument that whatever begins to exist has a cause and the universe began to exist.

Teleological argument

An argument from order or purpose in nature to an intelligent designer.

Fine-tuning argument

The argument that life-permitting physical constants are evidence of design.

Anthropic principle

The point that observers can only exist in conditions that permit observers.

Logical problem of evil

Mackie's claim that God's attributes are inconsistent with the existence of evil.

Evidential problem of evil

Rowe's argument that apparently pointless suffering makes God's existence improbable.

Free will defense

Plantinga's argument that God may permit evil because free creatures are valuable.

Soul-making theodicy

Hick's view that suffering allows moral and spiritual growth.

Skeptical theism

The view that human limits make us unable to judge whether evils serve a hidden good.

Evidentialism

Clifford's view that belief is justified only when supported by sufficient evidence.

Pascal's Wager

The argument that believing in God is a rational bet given the possible infinite reward.

Properly basic belief

A belief that is rational without being inferred from other beliefs.

Sample practice questions

30 more questions like these, from level 1 to 5, are in the practice set.