[1] Born in Bunzlau, Silesia, Liess received his doctorate in 1965 from the Ludwig-Maximilians-Universität in Munich with the thesis Der frühromanische Kirchenbau des 11.
He habilitated in 1970 with a thesis on Wahrheit und Wirklichkeit in der Kunst des P.P.
From March to June 2001, he took a German Academic Exchange Service (DAAD) at the National University of Cuyo in Mendoza (Argentina).
He was particularly interested in the planning history of the Strasbourg Cathedral and the person of Erwin von Steinbach.
Drei Studien zur niederländischen Kunst; In 2003 Im Spiegel der "Meninas".