# Criterion for Reality We need to develop reasons for accepting or rejecting the existence of entities that may appear in contending theories; in other words, we need a **Criterion for Reality**. We should not, of course, expect to find a final or an infallible criterion. Our judgements of what is or is not real always depend on the various explanations that are available to us, and sometimes change as our explanations improve. One of the most famous examples of this is that [Newtons Force of Gravity Is Not Real, But Einsteins Curvature of Spacetime Is Real](Newtons%20Force%20of%20Gravity%20Is%20Not%20Real,%20But%20Einsteins%20Curvature%20of%20Spacetime%20Is%20Real.md). Not only do explanations change, but our criteria and ideas about what should count as an explanation are gradually changing (improving) too. So the list of acceptable modes of explanation will always be open-ended, and consequently the list of acceptable criteria for reality must be open-ended too. But what is it about an explanation — given that, for whatever reasons, we find it satisfactory — that should make us classify some things as real and others as illusory or imaginary? The best criteria that we have found so far is [Dr Johnsons Criteria](Dr%20Johnsons%20Criteria.md). Note that this is a criterion for [Epistemological](Epistemology.md) reality, not [Ontological](Ontology.md) reality. However, the former approaches that latter with no limit, as explained in [Newtons Force of Gravity Is Not Real, But Einsteins Curvature of Spacetime Is Real](Newtons%20Force%20of%20Gravity%20Is%20Not%20Real,%20But%20Einsteins%20Curvature%20of%20Spacetime%20Is%20Real.md). --- Date: 20241020 Links to: [Fabric of Reality](Fabric%20of%20Reality.md) chapter 4, [Dr Johnsons Criteria](Dr%20Johnsons%20Criteria.md) Tags: References: * []()