This unique plotter and hand-coloured work by Harold Cohen merges algorithmic generation with artistic intuition and reflects a distinct moment in Cohen’s exploration of machine-generated forms. It likely comes from the group of works on paper informally known as the “Rocks” works. This particular composition bears more isolated forms than usual and a greater open space, being a signifier of the early development of the series.

The “Rocks” emerged from a transitional phase in AARON’s development. While Cohen began conceptualising AARON as early as 1972 and began coding at Stanford’s AI Lab in 1973, it wasn’t until the early 1980s that he implemented a new drawing method internally referred to as AARON II. This approach shifted away from the earlier “drawing primitives”, often likened to petroglyphs, toward a process that involved first generating an internal structure, then outlining it with a continuous line. In some works, the internal structure was retained; in others, only the outer contour remained, producing the biomorphic, rock-like formations seen here. For the hand-coloured versions Cohen used bold, expressive colour to deepen the formal relationships between the shapes, while preserving the structural machine-generated line work.

At the time only a small number of AARON outputs were hand-coloured, specifically those
the artist found visually compelling or compositionally successful. This selective approach
underscores Cohen’s role not just as a programmer and an artist, but as an active curator of
AARON’s creative output. This piece likely predates the 1982 exhibition at the deCordova
Museum in Lincoln, USA, which marked a public milestone for AARON’s development, and
delved into the investigations of co-authorship between artist and machine.