In Baumgarten's sketch of ontology we have progressed into the section on internal disjunctive predicates, that is, to the most general classification of all things. We have actually witnessed already one of these classifications, namely, the division of things into singular or universal, which with Baumgarten can be roughly identified with the division into actual and merely possible things.
Another important distinction for Baumgarten is the one between necessary and contingent matters, which is actually a somewhat dual classification in Baumgarten's philosophy. Firstly, there is the classification of necessary and contingent features of all things. Transcendental characteristics, which belong to all things whatsoever, are clearly necessary. In particular, all essences and attributes are necessary – this means only that the realm of possibilities is inevitably fixed and what is possible, must also be possible. Modes, on the other hand, are contingent, because one and the same thing can have different modes at different times.
This classification of features leads then to a similar classification in relation to things. Necessary things are such that have only necessary features, that is, which have only an essence and attributes, but no modes. Contingent things, on the other hands, have modes and are thus not necessary. We might also describe this differentiation in terms of mutability. Modes are such things that can change, that is, a thing might have this mode now, but something else later. In other words, modes are features that can vary, and things with such features can change them. Thus, contingent things are mutable. Necessary things, on the other hand, have no features that could change and are therefore immutable.
Another distinction having a close connection with the distinction of necessary and contingent is that between reality and negation. Actually, these terms form more like a scale, at the other end of which would be found complete negation, that is, a thing which cannot be described through any positive predicates. Baumgarten notes that such a thing would be actually nothingness, that is, such an entity doesn't actually exist, but all possible things are real or positive in some measure.
The scale of reality is then formed by noting how much negation is added to realities in a thing. At the other end of the scale, there is a completely positive thing with nothing negative in it, in other words, which is not limited by anything (this means obviously God). Other things, then, are sort of mixtures of positive and negative features.
Now, these negative features are either necessary to the thing having them or not. Necessary negations concern the essence or attributes of something – for instance, human beings have necessary negation of mortality. Baumgarten notes that the contingent negations or privations must then concern modes – for instance, if a certain person is blind, this is just a privation, because it doesn't belong to the essence of humanity to be blind. While all negations are bad things or evil, necessary negations are what Baumgarten calls metaphysical – they are inherent in the nature of things and thus something of which we cannot complain. Privations, on the other hand, are true defects, because they are defects that things ought not to have.
The idea of a scale going from absolute negation to absolute reality is no mere figure of speech for Baumgarten, because he truly thinks that one could quantify such intensive notions like reality and negation. This is part of Baumgarten's Wolffian heritage, in which mathematics is seen as a key point in all properly scientific research. Indeed, Baumgarten goes even farther than Wolff and with every metaphysical topic provides explanations what would be a unit of quantity for that notion and what meaning the ”greater-lesser” -relation would have with it. Thus, for instance, in a minimal ordering a minimal reality is grounded on another minimal reality and adding both units of reality and grounding relations will make for a more complex order (unfortunately, Baumgarten does not consider the question what to do in cases where the comparison of structures is not so easy – if order A has more units of reality than B, but C has more grounding relations than either, while still less realities than A, how should we compare quantities of A and C?).
Next time I'll continue with the division of substances.