Introduced in Modern Painters II (1846), the associative imagination is that faculty which 'seizes and combines at the same instant... all the important ideas of its poem or picture; and while it works with any one of them, it is at the same instant working with and modifying all in their relations to it, never losing sight of their bearings on each other' ( Works, 4.236). The development of this concept of Ruskin 's is linked with his appreciation of the unity of the Liber Studiorum. (See also Ruskin's introduction to the Liber Studiorum, and The Liber Studiorum and the associative imagination.)