yeah. As I mentioned to Carrol already in an aside, it's not a psychological concept. Rather, purity and danger are the anthropologist Mary Douglasn's names for the ways people in all societies categorize: there are good, pure things and then there are dirty, dangerous things. Totem and Taboo. Raw and the Cooked. Humans, because we cannot possibly process all the information that surrounds us, end up using categories to interpret the world into order/disorder, pure/dangerous, totem/taboo, clean/dirt, sacred/profane. [1]
It is really no different than what Carrol describes as our necessary reaction to tons of information. We can't process it all, so we end up filtering it by turning to what we've determined are trusted sources.
But it all can be boiled (cooked!) back down to the basic human condition: too much information - e.g., sensory data. To much data, disorder, chaos, noise.
Too much "dirt". Which is to say, Mary Douglas says that dirt is just a name for chaos.
We seek out ways of ordering, cleaning, purifying, trusting, winnowing, cooking it up in order to, uh, consume it. :)
ALL people live in societies that have created elaborate systems for imposing order on chaos - the microlevel of human social interaction - our exchanges with one another - can all be understood as interaction rituals that uphold order - be it the order of a dominant /hegemonic ideology or the order created by a _social movement_ or _social organization_ that actively tries to overthrow/undermine/subvert a dominant social order:
Douglas writes: "If we can abstract pathogenicity and hygiene from our notion of dirt, we are left with the old definition of dirt as matter out of place. This is a very suggestive approach . It implies two conditions: a set of of ordered relations and a contravention to that order. Dirt then, is never a unique, isolated event. Where there is dirt there is system. Dirt is the byproduct of a systematic ordering and classification of matter..."
"To conclude, if uncleanness is matter out of place, we must approach it through order. Uncleanness or dirt is that which must not be included if a pattern is to be maintained. To recognize this is the first step towards insight into pollution. It involves us in no clear-cut distinction between sacred and secular."
By extension, sociologists and anthropologists study how groups, organizations, and social movements to *create* dirt through ritual interactions the purpose of which is to create social solidarity, order, regularity, norms, standards.
And as I have said many times before, if you want to find where oppression operates, then look at norms, what is normalized, taken for granted, considered just the way it is.
[1](If you want to get social psychological about it, the argument is that societies more or less tend toward strong/harsh tendencies for splitting based on the way children are raised. If they are raised in the daddy-mommy-me formation of the hetnuke family the tendency toward this harsh splitting is more pronounced than if children are raised with lots of caregivers. blah blah.)