the Art History Chair at Basel. He is credited with having introduced the teaching method of using twin parallel projectors in the delivery of art history lectures, so that images could be compared when magic lanterns became less dangerous. Sir Ernst Gombrich recalled being inspired by him, as well as Erwin Panofsky. Notable students of Wölfflin include Klara Steinweg. Principles of Art History In Principles of Art History, Wölfflin formulated five pairs of opposed or contrary precepts in the form and style of art of the sixteenth and seventeenth centuries which demonstrated a shift in the nature of artistic vision between the two periods. These were: From linear (draughtsmanship, plastic, relating to contour in projected ideation of objects) to painterly (malerisch: tactile, observing patches or systems of relative light and of non-local colour within shade, making shadow and light integral, and allowing them to replace or supersede the dominance of contours as fixed boundaries.) From plane to recession: (from the 'Will to the plane', which orders the picture in strata parallel to the picture plane, to planes made inapparent by emphasising the forward and backward relations and engaging the spectator in recessions.) From closed (tectonic) form to open (a-tectonic) form (The closed or tectonic form is the composition which is a self-contained entity which everywhere points back to itself, the typical form of ceremonial style as the revelation of law, generally within predominantly vertical and horizontal oppositions; the open or atectonic form compresses energies and angles or lines of motion which everywhere reach out beyond the composition, and override the horizontal and vertical structure, though naturally bound together by hidden rules which allow the composition to be self-contained.) From multiplicity to unity: ('Classic art achieves its unity by making the parts independent as free members, and the baroque abolishes the uniform independence of the parts in favour of a more unified total motive. In the former case, co-ordination of the accents; in the latter, subordination.' The multiple details of the former are each uniquely contemplated: the multiplicity of the latter serves to diminish the dominance of line, and to enhance the unification of the multifarious whole.) From absolute clarity to relative clarity of the subject: (i.e. from exhaustive revelation of the form of the subject, to a pictorial representation which deliberately evades objective clearness in order to deliver a perfect rendering of information or pictorial appearance obtained by other painterly