Broadly speaking, relativism is the view that, at least in some domains, everything or every truth is relative to some standards so that, when two or more people disagree about these issues, they may all be correct (Siegel 2011; Boghossian 2006; Baghramian and Carter 2016). Epistemic relativism is the form of relativism that takes epistemic properties or norms also to be relative. While this approximate characterization of the position gives a flavor of the view, it hides the complexities and difficulties involved in precise formulations of the position that are not open to immediate refutations.
Relativism is of epistemological import in at least three distinct ways. First, one may be concerned with the epistemology of domains in which relativism is taken to be true. Thus, one may, for instance, wonder whether, if relativism is true, anything goes. One may also attempt to explain how faultless disagreement (disagreement between debaters who are all correct in their views) is genuinely possible and not tantamount to a change of subject (Kölbel 2004). Relatedly, one may worry whether rational debate can take place among individuals beheld by different epistemic frameworks or standards (Rorty 1980; Pritchard 2009).
Second, one may evaluate the arguments for, or against, relativism. The existence of obvious variations in the epistemic standards adopted at different historical times and by distinct cultures is often cited as evidence in favor of relativism. This evidence is strengthened by an appreciation of the depth and stubbornness of these differences. True, they may point to the irrationality of humanity. However, they would seem to be best explained by the lack of universal authoritativeness of any specific set of epistemic norms (Baghramian and Carter 2016). Additional evidence for relativism is provided by an analysis of the dialectic of debate. Those who attempt to defend the validity of their epistemic standards against opponents have no alternative but to deploy those very standards in their reasoning. Therefore, any defense of a system of knowledge or belief might be epistemically circular and thus ultimately illegitimate even by one’s own standards (see Boghossian 2006, 79). Overall, philosophers have been as hostile to relativism as they have been to skepticism. The literature is replete with arguments purporting to show that relativism is ultimately self-refuting, either because it cannot be coherently stated or because, if nothing is true absolutely, then the truth of relativism itself is at best relative and thus unpersuasive (Siegel 1987).
Third, one may interpret relativism as a metaepistemological position. Thus conceived, relativism is a thesis about epistemic norms or standards. For instance, the relativist may hold that whether being stated in the scriptures counts as indefeasible evidence for the truth of a claim depends on which epistemic norms are authoritative for a person (Rorty 1980). This statement of relativism may be interpreted descriptively to mean that individuals hold themselves to different standards (Barnes and Bloor 1982), but it may also be read normatively. In this latter interpretation, epistemic norms or standards are not universally authoritative, but govern the intellectual lives of some groups and not others.
More recently, novel relativist accounts of the truth of knowledge attributions (i.e., sentences that attribute to some S knowledge that p, for some proposition p) have proliferated. Most prominent among these are the views held by Max Kölbel (2004) and John MacFarlane (2011), for whom truth is relative to contexts of assessment.