A 1974 smoke and soot drawing by Otto Piene, featuring ethereal, atmospheric forms created through the controlled combustion of carbon.

This work, titled 'Yes' and dated 1974, exemplifies the experimental approach of Otto Piene, a co-founder of the ZERO group. Piene is recognised for his innovative use of fire and smoke as primary artistic media. Rather than relying on traditional pigments, he utilised the controlled combustion of candles or torches to deposit soot onto the paper surface. This technique creates ethereal, atmospheric effects that appear to hover between the physical material and the void. The composition features a central, organic form that emerges from a cloud of carbonised particles. The edges of the shape are soft and diffused, suggesting a sense of movement or a fleeting moment captured in time. The monochromatic palette, ranging from deep, opaque blacks to delicate, translucent greys, provides a sense of depth and volume. The soot particles create a unique texture, with areas of dense accumulation contrasting against lighter, wispy trails that dissipate towards the margins of the sheet. Piene's practice was concerned with the elemental forces of nature and the interaction between light and shadow. By employing smoke, he moved away from the gestural application of paint, allowing the physical process of burning to dictate the final appearance of the work. This method results in a visual language that is both precise and unpredictable. The work invites the viewer to observe the subtle gradations of tone and the delicate layering of soot, which evoke a sense of cosmic or microscopic phenomena. As a representative piece from his later career, 'Yes' demonstrates his continued exploration of light, space, and the transformative power of fire, maintaining the conceptual rigour that defined his contribution to post-war European art.