Is there a Brentanian model for Anton Marty's idea of general grammar? In some rare texts, among which "Meine letzten Wünsche für Österreich", Brentano alludes to the "characteristica universalis", mentioning Leibniz (and strangely Descartes), as the forerunners of some relevant aspects of his descriptive psychology. More exactly, Brentano uses the idea of "characteristica universalis" to suggest an analogy between psychological phenomena and words, insofar as they both result of the combination of psychological components. I suggest that in those passages, we see emerging the basic opposition between two models applied to (descriptive) psychology, i.e. the "morphological model" and the "syntactical model". On one hand there is obviously the model of composition of words out of letters, in reference to the combinatorial idea of "characteristica universalis". On the other hand, there is, as a potential alternative, the model inspired by the composition of sentences out of words, which is the core idea of the general grammar, developed by Marty. From this starting point, and in view of the scarsity of Brentanian texts on that topic, the question of the model of general grammar deserve to be adressed not only with respect to its textual origins in Brentano, but also by contrasting Brentano's position with its possible alternatives. In this paper, I intend to confront Brentano, Marty and Husserl’s positions, as for their references to Descartes, Leibniz and Port-Royal; each of these references suggesting a different pattern to understand the connection between general grammar and descriptive psychology. To what extent can one say that the kind of a priori characterizing the laws of descriptive psychology is the foundation of a certain type of general grammar? This question will lead us to contrast Brentano and Marty which, from the same basis, choose different references, in order to present the possibility of "characteristica universalis" (for the former) or of general grammar (for the latter). Furthermore, if we are not off the mark, it will turn out that while Brentano and Marty disagree on that point, Husserl, from references apparently similar to Brentano's ones, defends a position radically opposed to both Brentano and Marty.