Heterotopias indicate boundaries of practices and boundaries of ideas. Heterotopias as spatial realities confront us with the need to undo established syntax and linguistic categories as they do not exhaust in any a priori manner all the possibilities open to visual experience. New orderings are always possible which fall outside our customary expectations. These heterotopias demonstrate that our sense of order does not have any absolute foundation or standard of accuracy.
**uploaded 10 June 2020; revised 7 September 2020
Systems of enclosure 圍攏的系統：內外分界，裏外相連
A heterotopia is in some sense isolated from the rest of the world. Enclosure is extremely important.  This separation is sometimes marked by actual walls (prisons, schools, football stadiums), barbed wire (concentration camps), and the presence of guards (prisons, government buildings). There may be strict systems of rules, such as those of a game or a political group, which segregate the space from the rest of society. The use of religious or magical practices may also differentiate a specific space from the outside world. For instance, the White Lotus groups in China used elements from folk religion, including charms, healing rituals, incantations and so on. Some of those groups maintained a strict vegetarian diet and worshipped deities in congregational halls.  Every sacred space, for instance a church, a temple, a sacred garden, even a cemetery, is a heterotopia. Sacred spaces are demarcated from ordinary “profane” spaces by a boundary or threshold that is often taken to be absolute.  We can in this sense think of the zone in Tarkovsky’s film Stalker as a heterotopia.
Every heterotopia has relations to the rest of society, and in this sense to all other places. The nature of these relations is multifarious. There are many different ways of relating to other sites. For instance, the cemetery is separate from the rest of the community, but it nonetheless relates to other locales in the sense that every family has a place assigned in it, or at least has some relatives or friends in it.
Heterotopias retain some channels of communication with the outside world. They often contain more or less strict conditions of entry. In some instances, admittance is compulsory. For instance: the prison, the mental hospital for the criminally insane, and the army barracks in countries where military service is compulsory. In other cases, admittance requires some sort of official permission. There are criminal societies, guilds and trade unions, clubs, urban subcultures, and even artistic groups with fairly strict membership conditions. In virtue of this complex system of exclusions and rules of entry, a space can take on an almost religious aura. Other heterotopias require ritual purification. Access to a temple, for instance, may be restricted to men who have performed certain rites. They may be closed to members of particular social groups considered “impure” or “unclean”. There may be purely hygienic restrictions that have nothing religious about them. A sauna may only allow people who must first take a shower. Prospective entrants may need to pass some sort of trial or examination, as in the case of most universities. In a very different manner, spaces may also open up to the rest of society by borrowing well-known elements from popular or elite culture. For instance, religious sects in China often drew on stories, beliefs, and characters from operas and novels like The Water Margin. 
Two types of heterotopias 兩種異托邦：危機的，偏離的
「危機」的異托邦會因應特定時代一個社會裡公認的困難而出現。如今村昌平的電影《楢山節考》(1983) 裡描述的為行經和待產的婦女、少年男子、老者、寡婦特設的分隔場所，還有閾限的、過渡性的短暫空間如喪禮、婚禮、洗禮、成年冠禮等，以至為頑童設立的寄宿學校，到近期因 COVID-19 14天隔離而出現的居所。「偏離」的異托邦是為那些偏離了道德規範而作出特別隔離的空間。不過，「偏離」的異托邦不一定是強迫性加入的，可以是出於自願的退隱。對福柯來說，退休的院舍可說是上述兩者兼備的空間；一方面來說，年老是一種「危機」，另一方面，因年老而來的閒懶、缺乏生產力就是「偏離」社會正常的標準。
Heterotopias are thus systems of separation or isolation from, and communicating with, the outside world. The relationship between heterotopias and the world characterizes two particularly important types of spaces.
Movie still from 1958 version of The Ballad of Narayama 楢山節考 by Keisuke Kinoshita (image source…) In a certain part of Japanese society, elderly people elect to remove themselves from society in order to reduce the burden on the young. Social convention forced those over 70 years old are forced into a ritual suicide.
First of all, there are crisis heterotopias. These are holy, secluded, or forbidden places that are reserved exclusively for those who are socially regarded as being in some state of crisis. These may be menstruating women, adolescent boys, pregnant women about to give birth, elderly people, widows, etc., as in both movie versions of The Ballad of Narayama (1958, 1983). Boarding schools for the young can be considered crisis heterotopias to the extent that adolescence is treated as a critical and dangerous period in a person’s life. A space that is quarantined, for instance due to the outbreak of an epidemic, thereby becomes a crisis heterotopia. We may perhaps broaden this category by including all “liminal” spaces. These are sites associated with transitional states and rites of passage, such as marriages, funerals, christenings, and initiation rituals.  So the crisis heterotopia is closely connected with whatever a society classifies as a critical stage or condition. Different societies may have different understandings of what it means to have reached such a state.
The second type consists of deviation heterotopias. These places are reserved for individuals who either depart from some statistical mean or transgress some norm or standard. Examples include prisons, reform schools, and mental hospitals. Note that the relevant criteria—departure from the mean or transgression of a norm—do not play a part in crisis heterotopias. A crisis state like old age or adolescence or pregnancy is not a transgression or a deviation: rather it often constitutes a norm for all members of a certain group. Every person must go through adolescence. So crisis and deviation heterotopias are quite distinct. One important qualification: A space of deviation need not involve the compulsory confinement of the deviant. The deviant may have selected the site on purpose to engage secretly in certain transgressions. For instance, the four friends in Sade’s novel One Hundred and Twenty Days of Sodom intentionally retreat into an isolated, virtually inaccessible mountain castle where they give free vent to their violent sexual desires. In Bertolucci’s film The Last Tango in Paris, the central couple meets regularly in a Parisian apartment building, which represents a self-contained environment cut off from the rest of everyday life. Many films (arguably Oshima’s In the Realm of the Senses) highlight the isolation of the erotic relation from ordinary human society.
These two kinds of heterotopias are not mutually exclusive. Borderline cases partake of features belonging to both crisis heterotopias and deviation heterotopias. Foucault’s own example is the retirement home. On the one hand, old age is considered as a critical period, and so these are sites of crisis; on the other hand, however, idleness transgresses the norms of a society that only values work and leisure, so in a sense old age constitutes a deviation.
It is not clear, however, whether these two types exhaust all possible heterotopias, or whether Foucault highlights them only as particularly interesting or important cases. It is difficult to classify all instances mentioned by Foucault as either deviation or crisis heterotopias. For instance, what about the cinema? We could perhaps say that death and destruction are crises, and that the cinema is meant to preserve images of things and events which would otherwise disappear, so the cinema is a crisis heterotopia, but this thesis seems contrived. Foucault’s own examples are not always easy to classify into crisis or deviation heterotopias. In what sense is the Persian garden (see below) a crisis or a deviation heterotopia? I shall assume here that the division into crisis and deviation heterotopias is not meant as an exhaustive one.
Assemblage heterotopias 聚合的異托邦
Geometric structure of Persian garden plan: the Plan of Fin Garden, Kashan (Khansari et al. 1998). Source: “Persian Gardens: Meanings, Symbolism, and Design” (Farahani, Motamed, Jamei)
A heterotopia can juxtapose several incommensurable places. It brings them together in the same physical location. Foucault’s main example is the Persian garden: It “was a sacred space that was supposed to bring together inside its rectangle four parts representing the four parts of the world… The garden is the smallest parcel of the world and then it is the totality of the world.” 
The garden is meant to provide a general model of the world. It supplies a general structure, a sort of grammatical system, which gives a way of seeing and describing the entire universe. The modern zoological garden, which contains a wide variety of animals from all continents, partakes of this totalizing or universalizing aspiration. The arrangement of animals in a zoo constitutes a survey of the various animal species of the world. They are not representations, in the sense of imaginary or fictional entities; they are actual, living animals. But they are representatives, in the sense that they are function as examples of broader categories that have been gathered together in one single place. The use of particular cases as “examples” of a whole way of thinking is an important feature of many heterotopias.
In this context, Foucault also mentions the theater, which brings several ordinarily separate places into the same space, as well as cinematic montages of diverse images. And there is also the fairground, a temporary site that juxtaposes “stands, displays, heteroclite objects, wrestlers, snakewomen, fortune-tellers, and so forth.”  The concept of a cinema of attractions, proposed by historian Tom Gunning, highlights the connections between early cinema and such popular forms of entertainment as the vaudeville, all of which are characterized by the succession of highly diverse “attractions”. A boat that brings together diverse types of people can also be viewed in this way: for instance the setting of Katherine Anne Porter’s 1962 novel Ship of Fools.
In this context, one can also refer to archives, museums, libraries, and cabinets of curiosity, which often aim to accumulate a vast array of highly diverse exemplars. These particular sites can often be viewed as instantiations of a modern desire for universal classification. Foucault writes. “The drawing up of ‘tables’ was one of the great problems of the scientific, political and economic technology of the eighteenth century: how one was to arrange botanical and zoological gardens, and construct at the same time rational classifications of living beings…”  Libraries and museums are designed to function as general archives.
It would, however, be a grave mistake to interpret heterotopias as spaces of freedom. Foucault includes prisons and cemeteries, for instance, as prototypical heterotopias. His main emphasis is not on their liberating or emancipatory character. Rather, the emphasis is on their disruptive quality with respect to ordinary spatiotemporal arrangements. That these other spaces are disruptive does not imply that they are liberating. Foucault’s thesis nonetheless asserts that heterotopias suggest “ruptures in ordinary life, imaginary realms, polyphonic representations.” In this sense, reflection on heterotopias can help to open up our social and political imagination to alternative modes of thought and action. 
NOTES | CITATIONS
 Discipline and Punish, 141.
 Joseph Esherick, The Origins of the Boxer Uprising, (Berkeley and Los Angeles: University of California Press, 1987), 40-3.
 This idea was explored by Emile Durkheim in his classic The Sacred and the Profane.
 Eshserick, 65.
 The classical discussion of liminality was developed by Victor Turner.
 See p. 6: Michel Foucault’s “Of Other Spaces: Utopias and Heterotopias” in Architecture /Mouvement/ Continuité, October 1984 (“Des Espace Autres,” March 1967 Translated from the French by Jay Miskowiec): https://web.mit.edu/allanmc/www/foucault1.pdf
 Ibid., p. 7
 Discipline and Punish, 148.
 See p. 275 in: Defert, D. (1997), ‘Foucault, Space, and the Architects’, in Politics/Poetics. Documenta X – The Book. Ostfildern-Ruit: Cantz Verlag, pp. 274–83.