How can we judge when evidence is adequate?

What this prompt is really asking

Each of the twelve TOK concepts gives you a different way into a prompt. These are the ones that do the most work here.

• Evidence

  Grounds of Knowledge · primary lens

  Adequacy is a threshold rather than a property, so the prompt asks who sets it and against what risk of being wrong.

  What is offered in support of a claim. Evidence is not the same as proof: it raises or lowers how likely a claim is, and its force depends on how it was gathered, what it was gathered for, and what else it is consistent with. Asking what would count as evidence against a claim is usually more revealing than listing evidence for it.

• Certainty

  Status of Knowledge

  The point at which evidence is called adequate is the point at which a community stops doubting, which is a decision rather than a discovery.

  The degree to which doubt about a claim has been closed off. Certainty is a state of the knower, not of the claim, which is why a claim can be true without anyone being certain of it and why confidence and reliability can come apart badly.

Where the knowledge framework bites

Reached through this prompt’s concepts, in the framework’s canonical order.

Scope

Evidence: What a field can find evidence for marks the outer edge of what it can be about. Questions whose evidence is unobtainable in principle do not become open questions within a discipline; they fall outside its scope, and often get reassigned to another area of knowledge or to no one.

Certainty: The certainty available in a field is a feature of the field, not a measure of its rigour. Mathematics can offer proof because of what it is about; the human sciences cannot, and reading that as a deficiency mistakes scope for weakness.

Methods and tools

Evidence: Every discipline's methods are, in effect, a definition of what it will accept as evidence. A controlled trial, a dated document and a proof step are all evidence, but the practices that produce them are not interchangeable, and a method that cannot generate a certain kind of evidence will systematically miss the claims that would have needed it.

Certainty: Methods do not only produce results, they produce a warranted level of confidence in them. Confidence intervals, error bars, source triangulation and the standards of proof are all machinery for saying how certain a knower is entitled to be.