In the 2002 book The Mind in the Cave, South African archaeologist David Lewis-Williams explored a transitional episode in early human history: the urge to create art, to carve bone and soft stones, or smear a mix of fat and ochre on to rock walls. Why, asked Lewis-Williams, would early humans crawl along narrow shafts in the darkness to paint in underground spaces few would see? His (controversial) theory was that these early artists were shamanic figures; that their paintings related to visions experienced in altered states of mind, achieved perhaps through intoxicants and rhythmic ritual; and that the wall of the cave was considered a membrane between the spirit world and the realm of the living.
The Mind in the Cave is one of the guiding texts for Hollow Earth, which explores the cave in art and art in the cave. The Nottingham location is significant: the city sits above a network of more than 800 caves, carved into soft sandstone and used at various times as homes for the poor, tanneries and beer cellars.
