Values are abstract (2.1.2), and you cannot obey an abstraction. Between "modesty is good" and what you actually wear on Tuesday there has to be something specific.

That something is a norm, and norms are where culture stops being an idea and starts being a set of instructions you follow without noticing.

The idea, in plain words

Two useful further distinctions before the main typology.

Prescriptive versus proscriptive. Some norms tell you what to do (stand when a judge enters; remove your shoes); others what not to do (do not interrupt; do not eat with the left hand in many societies). Proscriptions tend to be stated more explicitly, which is why lists of rules often read as lists of prohibitions.

Ideal versus real norms. The rule as stated, and the rule as actually followed. Every society has a speed limit and a real driving speed; a stated dowry prohibition and a practice; an official rule about queue-jumping and a tolerance for certain people doing it. The gap between ideal and real norms is not decay — it is a standing feature of social life, and mapping it is a research task (1.5.2).

Sumner's four kinds

In 1906 the American sociologist William Graham Sumner published Folkways, and gave us a classification still used today. Later writers added a fourth category. The scale is one of increasing moral weight.

Folkways — customs and etiquette

Conventional practices of ordinary life. How you greet, how you eat, how loud you speak, how you dress for the office, which fork, how long a handshake lasts (1.1.2), whether you face the front of the lift.

Test: breaking one makes you odd, not bad. The reaction is a raised eyebrow, a smile, a whispered comment, mild social awkwardness. You may be thought eccentric, foreign, badly brought up or young.

Folkways feel trivial and are not. They are the medium of ordinary coordination, the main channel through which class and origin are read off a person in seconds (2.1.13), and their violation is the fastest route to being marked as an outsider.

Mores — moral rules

Norms with strong ethical weight, understood as being about right and wrong rather than about custom.

Do not lie to those who trust you. Do not abandon your parents. Be faithful to your spouse. Do not take advantage of someone weaker. Do not steal from a neighbour.

Test: breaking one makes you bad, not odd. The reaction is genuine moral anger, damaged reputation, exclusion, sometimes a lasting change in how you are described as a person.

The distinction between folkways and mores is not fixed — it is exactly the kind of thing societies argue about, and items migrate. Smoking indoors moved from folkway to something close to a moral rule in a generation. In many places, divorce moved the other way.

Taboos — the unthinkable

The strongest prohibitions, whose violation produces not merely condemnation but disgust and horror — a reaction that feels physical rather than reasoned (which is exactly 1.1.3's finding about internalisation).

Incest is the most widely reported. Cannibalism. In particular societies: eating certain animals, contact between certain categories of people, entering certain spaces, uttering certain names.

Test: you cannot argue about it comfortably. People do not want to discuss whether it might be permissible; the question itself is offensive. This is the surest sign you are looking at a taboo rather than a strong moral rule.

Taboos are of enormous sociological interest because they mark the outer boundary of a moral universe, and because they show how completely a social rule can be installed in a body.

Laws — codified and formally enforced

Norms written down and enforced by an organised authority with the power to punish.

Test: the enforcement is formal — an official, a procedure, a specified penalty.

Three things to notice, because this is where beginners go wrong.

Laws often codify existing mores — murder and theft were wrong before they were illegal, and law here mainly adds formal machinery to something already enforced socially.

Laws sometimes contradict mores, and then you can watch a society argue with itself. Untouchability was prohibited in India's Constitution in 1950 and persists in practice; prohibition of alcohol has been repeatedly legislated and repeatedly defeated by norms; caste and dowry law tell the same story (6.2.9). This is 1.2.3's fast and slow layers in one place: law is a medium-speed layer, mores are slow.

And law can lead, changing what is sayable and claimable long before it changes what is common — which is why the "if behaviour didn't change, the law was pointless" argument is too quick (1.2.3).

Go deeper

Norms exist wherever people are, including where you least expect them

A finding that always surprises: there is no such thing as a group without norms. Even settings defined by rule-breaking generate dense normative orders very fast.

Prison yards, black markets, gangs, riots, hospital wards at night, online forums, refugee camps, queues that form spontaneously in emergencies — all develop rules about who goes first, who may speak, what is dishonourable, what is fair. Disaster research (1.2.1) found people forming orderly queues nobody instituted. Studies of illegal economies find elaborate norms of credit and reputation precisely because there is no legal recourse.

The implication, from 1.2.1: the alternative to one normative order is generally another one, not the absence of order.

The enforcement puzzle: why do people obey when nobody is watching?

Four mechanisms, and it is worth knowing all four because they suggest different ways norms can fail.

Internalisation — the norm has become your own preference, and violating it makes you uncomfortable (1.1.3). This is by far the most efficient mechanism and the reason societies need so few police.

Anticipated sanction — you expect a reaction, even a mild one, and adjust. Note that anticipation works even when the reaction would not actually come; much conformity is to an imagined audience (Mead's generalised other, 2.3).

Reciprocity and reputation — you will meet these people again, and being known as someone who breaks rules is expensive. This is why norm compliance is generally stronger in dense, stable networks than among strangers, and why anonymity changes behaviour.

Belief in legitimacy — you think the rule is right, which is different from fearing the consequence. Weber's concept of legitimacy (1.2.1) does the work here, and it explains why a rule perceived as unjust erodes even under heavy enforcement.

Who gets to break which norms — the sociology of exemption

Here is the part most textbook treatments omit, and it is where norms connect to power (Part 8).

Norms are not enforced equally. The same violation, by different people, produces different reactions — and the pattern is not random.

A senior person may interrupt; a junior may not. A wealthy patient's rudeness to hospital staff is tolerated; a poor patient's is a reason to withdraw care. A man raising his voice is decisive; a woman doing so is difficult. A high-caste person may transgress a rule of purity and be forgiven; the same act by a Dalit may bring violence. A famous person's eccentricity is charm; the same behaviour in a poor person is a symptom.

Two concepts capture this. Idiosyncrasy credit — accumulated standing that buys permission to deviate. And, from Part 10, labelling: the same act, differently labelled by whom it is committed by, becomes deviance or eccentricity or nothing at all (10.2).

So the practical research question is never only "what is the norm here?" but "for whom is this a norm, and who is exempt?" The distribution of exemption is a map of the local power structure, and it is often easier to observe than the power structure itself.

Norms as an object of study: Garfinkel's method

If you want to know a norm's real content, the surest method is to break it slightly and watch.

Harold Garfinkel built his breaching experiments on this (2.4.3, 5.4). Students were asked to behave as lodgers in their own homes, or to demand clarification of every ordinary remark ("What do you mean, how am I?"). The reaction was not amusement but distress and anger — because what was being violated was not a rule of politeness but the taken-for-granted background that makes interaction possible at all.

Garfinkel's finding matters for this whole lesson: much of what holds social life together is not a list of rules people know but a continuous, mostly invisible activity of making sense together. Norms are less like a rulebook and more like the shared assumption that there is a rulebook.

Use this method gently, and never on strangers who cannot consent.

Norms change, and they can change fast

Because norms are the medium-speed layer, they are where you can actually watch culture move within a lifetime.

Smoking indoors. Seatbelts. Drink-driving. Corporal punishment of children in schools. Whether it is acceptable to look at a phone during dinner. Whether a man may cry in public. Each of these shifted substantially within one or two generations, in many countries.

The mechanism is generally a combination: a change in law, a change in what is publicly sayable, visible exemplars, and a tipping point at which enough people expect the new rule that enforcing the old one becomes the deviant act. That last element is important — norms are held in place by expectations about others' expectations, which is why they can look immovable and then collapse quickly (1.2.3, 11.2).

Why it matters

It converts "that's just how things are done" into an analysable object. You can now ask, of any rule: which kind is this, who enforces it, what happens to violators, who is exempt, and what value is it expressing? That is five researchable questions where before there was a shrug.

It explains why some reforms fail and others succeed. A campaign that treats a taboo as a folkway will fail; so will one that treats a folkway as a moral crusade. The type of norm determines the instrument — information, law, exemplars, or a generation.

And it gives you the mechanism of belonging. Every group you will ever join has a normative order you will be expected to absorb without being taught. Knowing that you are looking for one — and that the fastest way to find it is to watch what produces the raised eyebrow — makes you unusually quick at reading a room.