Positive vs negative philosophy: can any a priori system ground the existence of what it analyzes, or must philosophy begin from the unprethinkable?

F.W.J. Schelling, answered from the texts and cited to the page.

The position in brief

Negative philosophy — Logic in Hegel's sense, also geometry, also any a priori science — determines essences, articulates concepts, traces necessary connections among possible determinations.1 It cannot of itself account for the that of being, the brute fact that anything exists. The world is "completely contingent both as a whole and in its parts; it cannot possibly be the impression of something which has arisen by the necessity of reason." The positive philosophy starts from the unprethinkable (das Unvordenkliche) — that which simply is, prior to any concept of it — and tracks the historical unfolding of being in mythology and revelation.2

The structural distinction (negative articulates the what; positive articulates the that) is independent of the theological-historical content (mythology + revelation as God's two epochs of self-disclosure).

Sources

  1. As I have already said, what is a priori incomprehensible, because it is conveyed through no anterior concept, will become a comprehensible being in God, or it arrives at its concept in God. That which infinitely exists, that which reason cannot hide within itself becomes immanent for reason in God. Until now we have called the negative philosophy primarily a science of reason.
    The Grounding of Positive Philosophy The Berlin Lectures, p. 222
  2. But to know in its own purity, through the exclusion of contingent being [Seyn], that this being itself exists above that being: this can no longer be a task of that negative science, but of a Grounding of Positive Philosophy iv. Compare this and the following argument with the twelfth and thirteenth lectures of the Introduction to the Philosophy of Mythology, especially I/5, pages 291, 313, 319, and 320.
    The Grounding of Positive Philosophy The Berlin Lectures, pp. 157–158

Where the argument is made

  • On the Nature of Philosophy as Science (1821, in Pfau's Idealism and the Endgame of Theory
  • the Erlangen Initia Philosophiae Universae of 1820-21 stands behind it), The Grounding of Positive Philosophy: The Berlin Lectures (Matthews, 2007), On the History of Modern Philosophy (Munich lectures from the late 1820s onward, Bowie's translation, 1994), Philosophy of Revelation (1841-54)

How the argument was received

Held with full force from the 1820s through the Berlin lectures of 1841-1843 and into the unfinished late lectures published posthumously by my son. Articulated in different forms: as the absolute subject in the Erlangen lectures, as the contrast between negative and positive philosophy in the Munich and Berlin lectures, as the necessity-of-mythology and freedom- of-revelation in the late religious philosophy. The contingency-of-existence point is the philosophical core; the historical-theological content instantiates the structure but is not its essence.