Reprint of the original Latin text Tentamina semiologica, sive quaedam generalem theoriam signorum spectantia (1789), edited, translated and with an Introduction by Robert E. Innis The 33 sections of this classic text by Hoffbauer have a twofold focus: a descriptive inventory of signs, and a comparison of the expressive and cognitive powers of different sign systems. Using his sign typology as a point of departure, Hoffbauer inquires into the elements of matter and form both necessary and adequate to arrive at a definition of the sign. His purpose in doing so is to present his own version of a general sign theory after pointing out significant errors and weaknesses in the characteristicae universalis of Leibniz, Becher, Toennis, Kalmar, etc. Against the background of criticism of the contemporary deductive sign theories of Lambert, Baumgarten, Mendelssohn, Daries, Wilkins, Kircher and others, Hoffbauer's general semiology gives shape to an outline of a deductive-hypothetical theory of signs. In this historical perspective, Hoffbauer's semiology is of outstanding importance and provides the opportunity to think through once again central and permanent problems of the general science of signs.