2. Analytical Introduction (15)

4. Division of logic
4.1. Essential division
4.1.1. Foundation of the division

a) Statement
Logic is formally divided based on the proximate foundation of second intentions, which is the various ways of being known in reality that follow from the operations of the mind and their products.

b) Demonstration
m1 The formal object of logic is made up of second intention relations
M1 but every relation (whether real or of reason) is formally divided according to its foundation.

(In a relation, 4 things should be distinguished: the subject, the term, the foundation, and the relation itself. For example, paternity has for its subject the father, for its term the son, for its foundation active generation, and for relation paternity itself. The foundation being what accounts for the being of the relation, it is from this that generic relations can be divided. On this problem, which is specifically metaphysical, see SM, 5, lect. 17, nn. 1001 - 1005; John of St Thomas, Ars logica, II, q. 17, art.3; q. 2, art. 2, in fine.)

C1=m2Therefore the formal object of logic is formally divided according to the foundations of the second intention relations;
M2 But second intention relations are founded on the being of the thing as known, thus on the products of the mind;
C2Therefore the formal object of logic is formally divided according to the various products of the mind.

4.1.2.

4.1.2. The division itself

a) Demonstrative exposition

m Logic is formally divided according to the various ways of being known of being in the mind
M But being can be known by the human intellect as human in three ways:
1 - in an abstract way, attributable to many subjects;
2 - in the way of composition between an abstract form and the subject to which it is attributed, or in the way of division between an abstract form and the subject of which it is denied;
3 - in the way of inference from two or more attributions, in such a way that there follows a conclusion, in which the link between the attributed form and the subject which receives the attribution are mediated by one or more middle terms;
C therefore logic is formally divided into three parts, corresponding to the three modes of the human mind knowing being, such that:

1 - a logic of the universal, ie the attirbutable concept;
2 - a logic of attribution, ie of the proposition which results from the composition or division between a predicated concept and a subject;
3 - a logic of argumentation, ie of argumentation which, linking two or more attributions, draws some conclusion, in other words a new attribution, in which the link between the predicated concept and the subject is mediated by one or more middle terms.

b) Outline of the course consequent to this division

A course in logic, of all things, should proceed logically, so we will follow the division which we have just finished founding and establishing. Therefore, we will dedicate a part of our study to each type of product of the mind and to the corresponding second intentions.