Harold Cohen is a British artist who has lived in California since 1968. His major interest has always been color. However, for several decades he also concentrated on the representation problem: How little effort in lines does it take to generate an image that people can easily recognize as representing something specific? In the early 1960s, Cohen had already been successful as a painter—convincingly demonstrated by his participation in the Venice Biennale 1966, as one of five representatives of the UK. In 1968 he came into close contact with the computer’s capabilities.
He moved to San Diego to work as a visiting professor in fine art at the University of California, San Diego. He soon met Jeff Raskin, who showed him what flowcharts could be good for. This episode ended when Raskin gave him a Ditran (Diagnostic Fortran) manual. Cohen continued to work on his own and began investigating methods of Artificial Intelligence for applications in fine art. In 1970 he met Edward Feigenbaum, who invited him to the AI Lab at Stanford University. There Cohen informally learned the programming language SAIL, which at the AI Lab was the most used for memory-intensive and real-time applications. Cohen needed this level of performance for the real-time exhibitions he was preparing.
During the 1970s, he constructed computer-controlled drawing machines. They controlled a “Turtle” moving on the floor. Different from the MIT Turtle Cohen’s device moved by spinning two wheels at different speeds, which resulted in very smooth curves. The Turtle, via a sonar navigation system, even knew where it was on the drawing—a feature necessary to control the device on an area of three by nine meters.
Cohen’s program, now called AARON, made its first public appearances at the Los Angeles County Museum in 1972, and the La Jolla Museum in 1973. For these occasions AARON controlled hand-built flatbed plotters. The Turtle first went on display at documenta VI at Kassel, Germany in 1977.
Cohen developed AARON into an enormously powerful and complex rule-based system. In the 1990s, the drawing machines were replaced by painting machines (now in the permanent collection of the Museum of Computing History in Mountainview, CA.). Typical subject matters were portraits of “imagined” people, as well as still-lifes.
In 2002, he abandoned the painting machines in favor of wide-format printers. Although, color had been central to his work all along it was not until 1985/86 that he began to see how a program without vision could become an expert colorist. The resultant rule-based system became intractable by the end of 2005, when he replaced it by an algorithm, which AARON has been using ever since.
1946-1948 Radar engineer in the Royal Air Force.
1948-52 Student of Fine Art at the Slade School, University College, London. Diploma in Fine Art in 1951.
1952 Abbey Scholarship allows him to spend six months in Rome, Italy.
1952-1954 Lecturer in Art History at the Camberwell School of Art, London.
1956-59 Painter and lecturer at various colleges in Great Britain, including the University of Nottingham.
1960-61 Fellowship from the Commonwealth Fund for a stay in New York.
1961-65 Instructor in Painting at the Slade School of Fine Art, University College, London
1965 Participates at documenta III in Kassel, Germany. Midcareer retrospective at Whitechapel Gallery, London. Tapestry commissioned by British Petroleum Company.
1965-1968 Visitor, Slade School of Fine Art; Departmental Visitor, Coventry College of Art.
1966 Represents England, together with four other artists, at the XXXIII Biennale di Venezia.
1968 Moves to San Diego, CA, USA. Visiting professor in fine art at the University of California, San Diego. First computer graphics.
1969 Full professor at University of California, San Diego. Head of the department of fine art until 1971.
1971 First appearance of »A Computer-Controlled Drawing Machine« at the Fall Joint Computer Conference.
1973-75 Visitor to the Laboratory for Artificial Intelligence at Stanford University (California).
1974 First version of computer program AARON. A rule-based system that Cohen develops over many versions into one of the most powerful, if not the most powerful expert system of all times.
1977 Second invitation to documenta (VI) in Kassel, Germany. Cohen demonstrates the Turtle.
1977-1978 Solo exhibition at Stedelijk Museum in Amsterdam, where he also presents the Turtle.
Late 1970s Aaron draws abstract images. Cohen is inspired by petroglyphs in Chantal Valley, Southern California.
1980s Aaron capable of drawing figurative images: Floral structures and humanoid figures.
From 1983 Aaron stimulates color decisions that Cohen adds to the automatic line drawings.
1994 Professor emeritus.
Although Harold Cohen is one of the first artists to consistently and incessantly explore the computer and to programme it himself, he did not participate in any of the important early computer art exhibitions. Despite his emphasis on algorithmic art with an important random component, Aaron’s works do not represent a break in Cohen’s artistic oeuvre.
(Adopted from Herzogenrath & Nierhoff-Wielk 2007:322)