LOL Best I can find on this is:

https://en.wikipedia.org/wiki/Particularism

Epistemological particularism is the view that one can know something without knowing how one knows it.[1] By this view, one's knowledge is justified before one knows how such belief could be justified. Taking this as a philosophical approach, one would ask the question "What do we know?" before asking "How do we know?" The term appears in Roderick Chisholm's "The Problem of the Criterion", and in the work of his student, Ernest Sosa ("The Raft and the Pyramid: Coherence versus Foundations in the Theory of Knowledge"). Particularism is contrasted with methodism, which answers the latter question before the former. Since the question "What do we know" implies that we know, particularism is considered fundamentally anti-skeptical, and was ridiculed by Kant in the Prolegomena.

Closely associated with Franz Boas and the Boasian approach to anthropology, historical particularism rejected the cultural evolutionary model that had dominated anthropology until Boas. It argued that each society is a collective representation of its unique historical past. Boas rejected parallel evolutionism, the idea that all societies are on the same path and have reached their specific level of development the same way all other societies have.[2] Instead, historical particularism showed that societies could reach the same level of cultural development through different paths.[2]

Boas suggested that diffusion, trade, corresponding environment, and historical accident may create similar cultural traits.[2] Three traits, as suggested by Boas, are used to explain cultural customs: environmental conditions, psychological factors, and historical connections, history being the most important (hence the school's name).[2]

Critics of historical particularism argue that it is anti theoretical because it doesn't seek to make universal theories, applicable to all the world's cultures. Boas believed that theories would arise spontaneously once enough data was collected. This school of anthropological thought was the first to be uniquely American and Boas (his school of thought included) was, arguably, the most influential anthropological thinker in American history.

Here's a nice quote Saidit will love:

What are the marks of a sick culture? It is a bad sign when the people of a country stop identifying themselves with the country and start identifying with a group. A racial group. Or a religion. Or a language. Anything, as long as it isn’t the whole population. A very bad sign. Particularism. It was once considered a Spanish vice but any country can fall sick with it.

By Robert A. Heinlein (1907-1988) in: 'Friday' [Dr. Baldwin] (1982)