In summulas Petri Hispani extemporaria et succincta explanatio and Dialectica: cum quinque vocibus Porphyrii Phenicis: Argyropilo traductore: a Joanne Eckio explanatione declarata. Two first editions of the commentaries of the German scholastic theologian and counter-reformer Johann Eck (1486-1543) on Aristotle's (384-322 BC) major works and on the work of the Spanish philosopher and physician Peter of Spain (13th century), who further studied ia economic issues or business ethics. Eck's interpretations of these old classics became new starting points for the teaching of philosophy (dialectics, logic) at German universities, laying the foundations for its modern conception in the future. Both volumes from the same office have two-colored title pages decorated with an identical woodcut by Hans Burgkmair (1473-1531) measuring 13 x 12.5 cm, a leading period woodcutter, a pioneer of chiaroscuro woodcut technique, a disciple of Martin Schongauer. Beautiful early renaissance typography, sections, sometimes two-column print are complemented by textual woodcuts, diagrams and diagrams, initials, numerous period manuscript marginals and two small drawings. On the front cover, ownership notes dated to 1577, resp. 1578, on the title of old manuscript notes in Latin and Greek.