This essay written by the art historian Hans Sedlmayr, the author of important critical works among which Verlust der Mitte (1948), was translated into English as Art in Crisis and has now been translated into Italian for the first time. In Das Licht in seinen kunstlerischen Manifestationen, a short essay printed in 1979 at Mittenwald by the Mäander Kunstverlag, the author sees art history "sub specie lucis". Going beyond the categories of individual space proposed by Riegl, Sedlmayr attempts to give «a definition of art [...] founded on light relationships».
In the first section unconscious or atonic relationships are distinguished from «consciously planned tonic» relationships of light to the work of art. The variable factors of the relationship art-light are seen «from the point of view of light»: 1) natural light; 2) light transformed and filtered in interiors; 3) artificial light and the art of light. From the point of view of the work of art, variable factors are taken into account: 1) materials; 2) form (this factor in dealt within the chapter concerning natural light); 3) colour; 4) the symbological meaning of light; 5) the metaphorical representation of light; 6) its taxonomy according to light relationships based above all on numbers.
In the second section the light materials characterizing the «phototropic» ages of art are analysed from an historical point of view.
In the third section the author studies light materials and the technical characteristics of light in their relationships to «light forms, motifs and symbols». It is an analysis of the sun motif recurring in different ages.
The fourth section examines the relationships of the work of art to the «metaphysical and mystical aesthetics of light» which «after Hellenism replaces the old myths». All this is exemplified in the analysis of a specific architectural work, the St. Denis chorus, and of a painting by van Eyck, the Holy Virgin in the Church.
The fifth and last section explores the impossibility of representing «the mysterious aspect of light» which in the 19th and 20th centuries characterizes the «loss of transparency».
Sedlmayr's text is introduced by R. Masiero and R. Caldura who analyse the complicated interactions between the Austrian scholar and some important cultural contemporary friends; special attention is given to the interpretation of the work of art.
A biographic and bibliographic appendix closes the essay.