YOOL founded the gallery "Black Cube" in 2005. Black cube instead of white cube should be program: The artist's works were not to be presented as usual in a quasi-sacred, white room of a museum, where (according to the philosopher Schopenhauer) one should stand in front of a work of art and wait until it speaks to one, as in the audience of a prince.

Rather, the gallery was to offer the possibility of attracting a non-art-affine audience, of being able to discuss different views on the design and content of the exhibited works in a contrarian manner, and also to take away children's and young people's shyness towards art.

The concept has been a complete success. In a lecture on the museum and gallery scene in Erlangen, art historian Dr. Harald Tesan described the Black Cube as the most important private gallery in the city.