This work attempts to deal with all the aspects under which Meier‹s ‹Vernunftlehre‹ (Doctrine of Reason) and the ‹Auszug aus der Vernunftlehre‹ (Excerpts from the Doctrine of Reason), written in 1752, the same year, can be considered. Kant used the ‹Excerpts‹ for his lectures on logic for 40 years. The first part deals with the environment at the University of Halle as well as the history of the development, sources publication and impact. As a rule, the ‹Vernunftlehre‹ is seen as being completely in the tradition of Wolffianism. However this makes it difficult to explain some of the work‹s features, above all his division into inventio, dispositio, elocutio and exercitatio. This work shows that Meier‹s ‹Vernunftlehre‹ was essentially defined by rhetorical tradition. The second part deals with its integration into Meier‹s complete works as well with the analysis of both texts, which also contain lessons from epistemology, aesthetics, poetics, hermeneutics and anthropology. This work is more than just a specialized study of Meier‹s logic, since it also presents Meier‹s work as a whole.