How does it tell truth from falsehood?

Test every claim: does it claim to be from God, is it preserved, is it consistent, is there evidence? Verify sources. What contradicts itself, or fails its own test, is false.

By testing: a claim deserves belief in proportion to its evidence, extraordinary claims require extraordinary evidence, and a claim that cannot be tested even in principle is treated with suspicion, not trust.

By proportioning belief to evidence, as Hume taught: strong evidence, firm belief; weak evidence, tentative belief; no evidence, no verdict. The distinctive agnostic move is the third step — where others feel forced to answer, the agnostic records the question as open.

By testing every claim against Scripture and the apostolic teaching fixed in the creeds — 'test everything; hold fast what is good' (1 Thessalonians 5:21) — and by fruits: Jesus said false teachers are known by what their lives produce (Matthew 7:15–20). Catholics and Orthodox add the church's teaching office as the final safeguard.

The Torah itself gives tests: a prophet whose prediction fails is false, and even a wonder-worker who calls to other gods must be rejected. Within the law, truth is settled by argument, evidence, and the majority ruling of the sages — the Talmud insists the Torah 'is not in heaven.'

By fruits and by consistency: teachings that lead to greed, hatred, and harm are to be abandoned; those that lead to welfare adopted. For doctrine, the Mahaparinibbana Sutta gives four tests — any claim must be checked against the discourses and the monastic rule before it is accepted.

By testing claims against the pramanas — does perception, inference, or trustworthy testimony support them — and, on ultimate matters, against shruti. The six classical schools (darshanas) debated one another for centuries under formal rules of argument, in a tradition of public disputation the culture prized.

By measuring everything against the Guru's teaching (gurmat) rather than the self-willed mind (manmat), and by the fruit a claim bears in life: the scripture says truth is high, but truthful living is higher still.

In public matters: open evidence, argument, and courts that must give reasons. In religious matters the state refuses to judge at all — Locke argued the magistrate has no competence over souls — so testing truth there belongs to citizens and their communities.

By evidence, logic, and open scrutiny: a claim earns belief in proportion to its evidence, and extraordinary claims need strong evidence. Willingness to be corrected is treated as the mark of honesty.

By open contest: evidence, argument, and the standing right of anyone to say 'you are wrong.' There is no court of final appeal; error is caught by keeping every question open to challenge.

By argument and evidence, as in any modern inquiry; some feminist scholars add that the experience of the disadvantaged reveals what the comfortable overlook (standpoint theory) — a method feminists themselves continue to debate.

It has no formal test; national narratives are checked, when they are checked, by ordinary historical evidence. Renan himself admitted that nations remember selectively — forgetting, he wrote, is part of nation-making — and historians have shown many 'ancient' traditions to be recent inventions.