Evidentialism and Rational Belief

The view that the rationality of religious belief depends on its being adequately supported by evidence.

Definition

The thesis that a belief, including a religious belief, is rational or epistemically justified only insofar as it is held in proportion to the evidence that supports it.

Scope

This topic covers evidentialism as applied to religious belief, including the Lockean and Cliffordian demand that belief be proportioned to evidence, the evidentialist objection that theism lacks sufficient evidence, and probabilistic defenses such as Swinburne's that aim to meet the demand. It does not cover reformed epistemology's denial of the demand, treated under reformed epistemology.

Core questions

• Should all beliefs be proportioned to the available evidence?
• Does theism meet the evidentialist standard of justification?
• What counts as adequate evidence for a religious belief?
• Can probabilistic argument satisfy the evidentialist requirement for theism?

Key theories

Cliffordian evidentialism

Clifford holds that it is wrong always, everywhere, and for anyone to believe anything on insufficient evidence, making evidential support a universal epistemic and even moral duty that religious belief must satisfy.

Probabilistic natural theology as evidentialist reply

Swinburne accepts the evidentialist framework but argues that the cumulative evidence of cosmic existence, order, and experience makes theism more probable than not, so religious belief can meet the evidential standard.

History

Evidentialism has Enlightenment roots in Locke's account of proportioning assent to probability, was given a stringent moral form in Clifford's 1877 essay, and underlies the modern evidentialist objection to theism associated with Russell and Flew. Swinburne's probabilistic program represents an attempt to satisfy rather than reject the requirement, while reformed epistemology arose to challenge it.

Debates

Whether the evidentialist requirement is self-defeating

Reformed critics argue that the demand to base every belief on evidence cannot itself be supported by evidence and is therefore self-referentially incoherent; evidentialists reply that the principle is a foundational epistemic norm.

Whether theism actually meets the standard

Swinburne argues the cumulative case renders theism probable, satisfying evidentialism; critics contend the arguments fall short, so by evidentialist lights religious belief is unjustified.

Key figures

• John Locke
• W. K. Clifford
• Bertrand Russell
• Richard Swinburne
• Antony Flew

Seminal works

• clifford1877
• swinburne1981
• plantinga1983

Frequently asked questions

What is the evidentialist objection to theism?

It is the claim that since rational belief requires sufficient evidence and the evidence for God is held to be inadequate, religious belief is irrational or epistemically unjustified.

How do theists respond to evidentialism?

Some, like Swinburne, accept the demand and argue that theism does meet the evidential standard; others, the reformed epistemologists, reject the demand itself as too strong and not met even by ordinary rational beliefs.