Allegory of the Cave
Blake used Plato's Allegory of the Cave in "Visions of the Daughters of Albion" as a theme for the three characters not being able to understand the true nature of reality, without being hindered by convention. It has been argued that Theotormon is a mythicised version of John Stedman, whose book about his experience of slavery and brutality in Suriname on the coast of South America was being illustrated by Blake at the time.