Metabolism (Japanese: メタボリズム, Hepburn: metaborizumu, also shinchintaisha (新陳代謝)) was a post-war Japanese biomimetic architectural movement that fused ideas about architectural megastructures with those of organic biological growth. It had its first international exposure during CIAM's 1959 meeting and its ideas were tentatively tested by students from Kenzo Tange's MIT studio.

During the preparation for the 1960 Tokyo World Design Conference a group of young architects and designers, including Kiyonori Kikutake, Kisho Kurokawa and Fumihiko Maki prepared the publication of the Metabolism manifesto. They were influenced by a wide variety of sources including Marxist theories and biological processes. Their manifesto was a series of four essays entitled: Ocean City, Space City, Towards Group Form, and Material and Man, and it also included designs for vast cities that floated on the oceans and plug-in capsule towers that could incorporate organic growth. Although the World Design Conference gave the Metabolists exposure on the international stage, their ideas remained largely theoretical.

Some smaller, individual buildings that employed the principles of Metabolism were built and these included Tange's Yamanashi Press and Broadcaster Centre and Kurokawa's Nakagin Capsule Tower. The greatest concentration of their work was to be found at the 1970 World Exposition in Osaka where Tange was responsible for master planning the whole site whilst Kikutake and Kurokawa designed pavilions. After the 1973 oil crisis, the Metabolists turned their attention away from Japan and toward Africa and the Middle East.

The Congrès Internationaux d'Architecture Moderne (CIAM) was founded in Switzerland in 1928 as an association of architects who wanted to advance modernism into an international setting. During the early 1930s they promoted the idea (based upon new urban patterns in the United States) that urban development should be guided by CIAM's four functional categories: dwelling, work, transportation, and recreation.^[1] By the mid-1930s Le Corbusier and other architects had moulded CIAM into a pseudo-political party with the goal of promoting modern architecture to all. This view gained some traction in the immediate post-war period when Le Corbusier and his colleagues began to design buildings in Chandigarh. By the early 1950s it was felt that CIAM was losing its avant-garde edge so in 1954 a group of younger members called "Team 10" was formed. This included the inner circle Dutch architects Jacob Bakema and Aldo van Eyck, Italian Giancarlo De Carlo, Greek Georges Candilis, the British architects Peter and Alison Smithson and the American Shadrach Woods. The Team 10 architects introduced concepts like "human association", "cluster" and "mobility", with Bakema encouraging the combination of architecture and planning in urban design. This was a rejection of CIAM's older four function mechanical approach, and it would ultimately lead to the break-up and end of CIAM.^[2]

Kenzo Tange was invited to the CIAM '59 meeting of the association in Otterlo, Netherlands. In what was to be the last meeting of CIAM, he presented two theoretical projects by the architect Kiyonori Kikutake: the Tower-shaped City and Kikutake's own home, the Sky House. This presentation exposed the fledgling Metabolist movement to its first international audience. Like Team 10's "human association" concepts, Metabolism too was exploring new concepts in urban design.^[3]

Tower-shaped City was a 300 metre tall tower that housed the infrastructure for an entire city. It included transportation, services and a manufacturing plant for prefabricated houses. The tower was vertical "artificial land" onto which steel, pre-fabricated dwelling capsules could be attached. Kikutake proposed that these capsules would undergo self-renewal every fifty years, and the city would grow organically like branches of a tree.^[3]

Constructed on a hillside, the Sky House is a platform supported on four concrete panels with a hyperbolic paraboloid shell roof. It is a single space divided by storage units with the kitchen and bathroom on the outer edge.^[4] These latter two were designed so that they could be moved to suit the use of the house—and, indeed, they have been moved and/or adjusted about seven times over the course of fifty years. At one point a small children's room was attached to the bottom of the main floor with a small child-sized access door between the two rooms.^[5]

After the meeting, Tange left for Massachusetts Institute of Technology to begin a four-month period as a visiting professor. It is possible that based upon the reception of Kikutake's projects in Otterlo he decided to set the fifth year project as a design for a residential community of 25,000 inhabitants to be constructed on the water of Boston Bay.^[6] Tange felt a natural desire to produce urban designs based upon a new prototype of design, one that could give a more human connection to super-scale cities. He considered the idea of "major" and "minor" city structure and how this could grow in cycles like the trunk and leaves of a tree.^[7]

One of the seven projects produced by the students was a perfect example of his vision. The project consisted of two primary residential structures each of which was triangular in section. Lateral movement was provided by motorways and monorail, whilst vertical movement from the parking areas was via elevators. There were open spaces within for community centres, and at every third level there were walkways along which were rows of family houses.^[7] The project appeared to be based upon Tange's unrealised competition entry for the World Health Organization headquarters in Geneva^[8] and both projects paved the way for his later project, "Plan for Tokyo – 1960". Tange went on to present both the Boston Bay Project and the Tokyo Plan at the Tokyo World Design Conference.^[9]

The conference had its roots with Isamu Konmochi and Sori Yanagi who were representatives of the Japanese Committee on the 1956 International Design Conference in Aspen, Colorado. They suggested that rather than a four yearly conference in Aspen there should be a roving conference with Tokyo as its first setting in 1960.^[10] Three Japanese institutional members were responsible for organising the conference, although after the Japan Industrial Design Association pulled out only the Japan Institute of Architects and the Japan Association of Advertising Arts were left. In 1958 they formed a preparation committee led by Junzo Sakakura, Kunio Maekawa and Kenzo Tange. As Tange had just accepted an invitation to be a visiting professor at Massachusetts Institute of Technology he recommended his junior colleague Takashi Asada to replace him in the organisation of the conference programmes.^[11]

The young Asada invited two friends to help him: the architectural critic and former editor of the magazine Shinkenchiku, Noboru Kawazoe, and Kisho Kurokawa who was one of Tange's students. In turn these two men scouted for more talented designers to help, including: the architects Masato Otaka and Kiyonori Kikutake and the designers Kenji Ekuan and Kiyoshi Awazu.^[12] Kurokawa was selected because he had recently returned from an international student conference in the Soviet Union and was a student of the Marxist architectural theorist Uzō Nishiyama. Ekuan was asked because of his recent participation in a seminar given by Konrad Wachsmann^[13] (he arrived at the lecture on a YA-1 motorbike that he had newly designed for Yamaha)^[14] and Otaka was a junior associate of Kunio Maekawa and had just completed the Harumi Apartment Building in Tokyo Bay. Fumihiko Maki, a former undergraduate student of Tange also joined the group whilst in Tokyo on a travelling fellowship from the Graham Foundation.^[15][16]

By day Asada canvassed politicians, business leaders and journalists for ideas, by night he met with his young friends to cultivate ideas. Asada was staying at the Ryugetsu Ryokan in Asakusa, Tokyo and he used it as a meeting place for progressive scholars, architects and artists. He often invited people from other professions to give talks and one of these was the atomic physicist, Mitsuo Taketani. Taketani was a scholar who was also interested in Marxist theory and he brought this along with his scientific theories to the group. Taketani's three stage methodology for scientific research influenced Kikutake's own three stage theory: ka (the general system), kata (the abstract image) and katachi (the solution as built), which he used to summarise his own design process from a broad vision to a concrete architectural form.^[17]

The group also searched for architectural solutions to Japan's phenomenal urban expansion brought about by its economic growth and how this could be reconciled with its shortage of usable land. They were inspired by examples of circular growth and renewal found in traditional Japanese architecture like the Ise Shrine and Katsura Detached Palace.^[18] They worked in coffee shops and Tokyo's International House to produce a compilation of their works that they could publish as a manifesto for the conference.^[19]

The conference ran from 11–16 May 1960 and had 227 guests, 84 of whom were international, including the architects Louis Kahn, Ralph Erskine, B. V. Doshi, Jean Prouvé, Paul Rudolph and Peter and Alison Smithson. Japanese participants included Kunio Maekawa, Yoshinobu Ashihara and Kazuo Shinohara.^[20]

After his 13 May lecture, Louis Kahn was invited to Kikutake's Sky House and had a long conversation with a number of Japanese architects including the Metabolists. He answered questions until after midnight with Maki acting as translator. Kahn spoke of his universal approach to design and used his own Richards Medical Research Laboratories as an example of how new design solutions can be reached with new thinking about space and movement. A number of the Metabolists were inspired by this.^[vague][21]

The Metabolism name

Whilst discussing the organic nature of Kikutake's theoretical Marine City project, Kawazoe used the Japanese word shinchintaisha as being symbolic of the essential exchange of materials and energy between organisms and the exterior world (literally metabolism in a biological sense.) The Japanese meaning of the word has a feeling of replacement of the old with the new and the group further interpreted this to be equivalent to the continuous renewal and organic growth of the city.^[15] As the conference was to be a world conference, Kawazoe felt that they should use a more universal word and Kikutake looked up the definition of shinchintaisha in his Japanese-English dictionary. The translation he found was the word Metabolism.^[22]

The group's manifesto, Metabolism: The Proposals for New Urbanism, was published at the World Design Conference.^[23] Two thousand copies of the 90 page book were printed and were sold for ¥500 by Kurokawa and Awazu at the entrance to the venue.^[18] The manifesto opened with the following statement:

Metabolism is the name of the group, in which each member proposes further designs of our coming world through his concrete designs and illustrations. We regard human society as a vital process—a continuous development from atom to nebula. The reason why we use such a biological word, metabolism, is that we believe design and technology should be a denotation of human society. We are not going to accept metabolism as a natural process, but try to encourage active metabolic development of our society through our proposals.^[24]

The publication included projects by each member but a third of the document was dedicated to work by Kikutake^[25] who contributed essays and illustrations on the "Ocean City". Kurokawa contributed "Space City", Kawazoe contributed "Material and Man" and Otaka and Maki wrote "Towards the Group Form".^[24] Awazu designed the booklet and Kawazoe's wife, Yasuko, edited the layout.^[26]

Some of the projects included in the manifesto were subsequently displayed at the Museum of Modern Art's 1960 exhibition entitled Visionary Architecture and exposed the Japanese architects' work to a much wider international audience.^[27]

Unlike the more rigid membership structure of Team 10, the Metabolists saw their movement as having organic form with the members being free to come and go. Although the group had cohesion they saw themselves as individuals and their architecture reflected this.^[28] This was especially true for Tange who remained a mentor for the group rather than an "official" member.^[29]

On 1 January 1961 Kenzo Tange presented his new plan for Tokyo Bay (1960) in a 45-minute television programme on NHK General TV.^[42] The design was a radical plan for the reorganization and expansion of the capital in order to cater for a population beyond 10 million.^[43] The design was for a linear city that used a series of nine-kilometre modules that stretched 80 km across Tokyo Bay from Ikebukuro in the north west to Kisarazu in the south east. The perimeter of each of the modules was organised into three levels of looping highways, as Tange was adamant that an efficient communication system would be the key to modern living.^[42][43] The modules themselves were organised into building zones and transport hubs and included office, government administration and retail districts as well as a new Tokyo train station and highway links to other parts of Tokyo. Residential areas were to be accommodated on parallel streets that ran perpendicular to the main linear axis and people would build their own houses within giant A-frame structures.^[44]

The project was designed by Tange and other members of his studio at Tokyo University, including Kurokawa and Arata Isozaki. Originally it was intended to publish the plan at the World Design Conference (hence its "1960" title) but it was delayed because the same members were working on the Conference organisation.^[45] Tange received interest and support from a number of government agencies but the project was never built.^[42] Tange went on to expand the idea of the linear city in 1964 with the Tōkaidō Megalopolis Plan. This was an ambitious proposal to extend Tokyo's linear city across the whole of the Tōkaidō region of Japan in order to re-distribute the population.^[46]

Both Kikutake and Kurokawa capitalised on the interest in Tange's 1960 plan by producing their own schemes for Tokyo. Kikutake's plan incorporated three elements both on the land and the sea and included a looped highway that connected all the prefectures around the bay. Unlike Tange however its simple presentation graphics put many people off. Kurokawa's plan consisted of helix-shaped megastructures floating inside cells that extended out across the bay. Although the scheme's more convincing graphics were presented as part of a film the project was not built.^[42]

With Japan's property boom in the 1980s, both Tange and Kurokawa revisited their earlier ideas: Tange with his Tokyo Plan 1986 and Kurokawa with his New Tokyo Plan 2025. Both projects used land that had been reclaimed from the sea since the 1960s in combination with floating structures.^[42]

The reconstruction plan of the capital city of Skopje then part of the Yugoslav Republic of Macedonia (now North Macedonia) following a major earthquake was won by Tange's team. The project was significant because of its international influence as well as an international model case for urban reconstruction. It is a major breakthrough for the Metabolist movement to realise their approach on an international scale.^[47]

Metabolism developed during the post war period in a Japan that questioned its cultural identity. Initially the group had chosen the name Burnt Ash School to reflect the ruined state of firebombed Japanese cities and the opportunity they presented for radical re-building. Ideas of nuclear physics and biological growth were linked with Buddhist concepts of regeneration.^[61] Although Metabolism rejected visual references from the past,^[62] they embraced concepts of prefabrication and renewal from traditional Japanese architecture, especially the twenty-year cycle of the rebuilding of the Ise Shrine (to which Tange and Kawazoe were invited in 1953). The sacred rocks onto which the shrine is built were seen by the Metabolists as symbolising a Japanese spirit that predated Imperial aspirations and modernising influences from the West.^[63]

In his Investigations in Collective Form Maki coined the term Megastructure to refer structures that house the whole or part of a city in a single structure. He originated the idea from vernacular forms of village architecture that were projected into vast structures with the aid of modern technology. Reyner Banham borrowed Megastructure for the title of his 1976 book which contained numerous built and unbuilt projects. He defined megastructures as modular units (with a short life span) that attached to structural framework (with a longer life span).^[64] Maki would later criticise the Megastructure approach to design advocating instead his idea of Group Form which he thought would better accommodate the disorder of the city.^[65]

The architect Robin Boyd readily interchanges the word Metabolism with Archigram in his 1968 book New Directions in Japanese Architecture.^[66] Indeed, the two groups both emerged in the 1960s and disbanded in the 1970s and used imagery with megastructures and cells, but their urban and architectural proposals were quite different. Although utopian in their ideals, the Metabolists were concerned with improving the social structure of society with their biologically inspired architecture, whereas Archigram were influenced by mechanics, information and electronic media and their architecture was more utopian and less social.^[65]

Japan was selected as the site for the 1970 World Exposition and 330 hectares in the Senri Hills in Osaka Prefecture were set aside as the location.^[67] Japan had originally wanted to host a World Exposition in 1940 but it was cancelled with the escalation of the war. The one million people who had bought tickets for 1940 were allowed to use them in 1970.^[68]

Kenzo Tange joined the Theme Committee for the Expo and along with Uso Nishiyama he had responsibility for master planning the site. The theme for the Expo became "Progress and Harmony for Mankind". Tange invited twelve architects, including Arata Isozaki, Otaka and Kikutake to design individual elements.^[67] He also asked Ekuan to oversee the design of the furniture and transportation and Kawazoe to curate the Mid-Air Exhibition which was sited in the huge space-frame roof.^[68]

Tange envisioned that the Expo should be primarily conceived as a big festival where human beings could meet. Central to the site he placed the Festival Plaza onto which were connected a number of themed displays, all of which were united under one huge roof.^[69] In his Tokyo Bay Project Tange spoke about the living body having two types of information transmission systems: fluid and electronic. That project used the idea of a tree trunk and branches that would carry out those types of transmission in relation to the city. Kawazoe likened the space frame roof of the Festival Plaza to the electronic transmission system and the aerial-themed displays that plugged into it to the hormonal system.^[70]

Kawazoe, Maki and Kurokawa had invited a selection of world architects to design displays for the Mid-Air Exhibition that was to be incorporated within the roof. The architects included Moshe Safdie, Yona Friedman, Hans Hollein and Giancarlo De Carlo.^[71] Although Tange was obsessed with the theory of flexibility that the space framed provide he did concede that in reality it was not so practical for the actual fixing of the displays.^[70] The roof itself was designed by Koji Kamaya and Mamoru Kawaguchi who conceived it as a huge space frame. Kawaguchi invented a welding-free ball joint to safely distribute the load and worked out a method of assembling the frame on the ground before raising it using jacks.^[72]

Kikutake's Expo Tower was situated on the highest hill in the grounds and acted as a landmark for visitors. It was built of a vertical ball and joint space onto which was attached a series of cabins. The design was to have been a blueprint for flexible vertical living based upon a 360m3 standard construction cabin clad with a membrane of cast aluminium and glass that could be flexibly arranged anywhere on the tower. This was demonstrated with a variety of cabins that were observation platforms and VIP rooms and one cabin at ground level that became an information booth.^[73]

Kurokawa had won commissions for two corporate pavilions: the Takara Beautillion and the Toshiba IHI pavilion.^[74] The former of these was composed of capsules plugged onto six point frames and was assembled in just six days; the latter was a space frame composed of tetrahedron modules, based upon his Helix City that could grow in 14 different directions and resemble organic growth.^[75]

Expo '70 has been described has the apotheosis of the Metabolist movement.^[68] But even before Japan's period of rapid economic growth ended with the world energy crisis, critics were calling the Expo a dystopia that was removed from reality.^[76] The energy crisis demonstrated Japan's reliance both on imported oil and led to a re-evaluation of design and planning with architects moving away from utopian projects towards smaller urban interventions.^[77]

After the 1970 Expo, Tange and the Metabolists turned their attention away from Japan towards the Middle East and Africa. These countries were expanding on the back of income from oil and were fascinated by both Japanese culture and the expertise that the Metabolists brought to urban planning.^[78] Tange and Kurokawa capitalised on the majority of the commissions, but Kikutake and Maki were involved too.^[79]

Tange's projects included a 57,000 seat stadium and sports center in Riyadh for King Faisal, and a sports city for Kuwait for the planned 1974 Pan Arab Games. However, both were put on hold by the outbreak of the Fourth Arab–Israeli War in 1973. Likewise, the plan for a new city center in Tehran was cancelled after the 1979 revolution. He did however complete the Kuwaiti Embassy in Tokyo in 1970 and Kuwait's International Airport, as well as the Presidential Palace in Damascus, Syria.^[80][81]

Kurokawa's work included a competition win for Abu Dhabi's National Theatre (1977), capsule-tower designs for a hotel in Baghdad (1975) and a city in the desert in Libya (1979–1984).^[82]

Kikutake's vision for floating towers was partly realised in 1975 when he designed and built the Aquapolis for the Okinawa Ocean Expo. The 100 x 100 meter floating city block contained accommodation that included a banquet hall, offices and residences for 40 staff and it was built in Hiroshima and then towed to Okinawa.^[83] Further unbuilt floating city projects were undertaken, including a floating city in Hawaii for ocean research and a plug-in floating A-frame unit containing housing and offices that could have been used to provide mobile homes in the event of a natural disaster.^[84]