Three excerpts from German Philosophy 1760–1860 The Legacy of Idealism, Terry Pinkard, 2002.

"The Kantian legacy, by taking normative authority to be self-legislated, to be a product of our spontaneity as it combines itself with our receptivity in the theoretical sphere and to be a product of our autonomy in the practical sphere, raised the issue as to whether that kind of normative authority could itself be secured against further challenge. Kantians had their own answer: this normative authority, although spontaneously generated and therefore self-imposed, is nonetheless that of a "universal self-consciousness" of the rules binding all rational agents, since without such rules we could not be self-conscious at all.... Post-Kantians,... moved to the idea... that as self-legislated, such authority,... is always subject to challenge. That universal self-consciousness cannot therefore be itself a matter of "certainty" but only of a certain kind of unavoidability, a capacity to withstand such challenges and to emerge as being authoritative for all,... as that which we,... come to find that we practically cannot do without (358–359).

"In Hegel's treatment, reasons come to be conceived as part of the thickly historical and social practice of giving and asking for reasons, and their universality was thereby conceived as a fragile historical achievement, not as a transcendental feature of consciousness.... In Hegel's story, this turns out to be the genesis of "us moderns," who are "destined" to understand normative authority in light of our growing self-consciousness about our own role in establishing such normative authority and therefore about its fragility and defeasibility (359).

"Kierkegaard's own existential reworking of the "Kantian paradox" is... what has come to matter to us absolutely in modern life is that we lead our own lives, individually and collectively, such that despair becomes our permanent condition of grasping... that this may be... an impossibility - despair about what ultimately matters to us not itself being achievable. The idealist faith (Kantian and post-Kantian) lay rooted in the concept of the achievability of self-determination, and, in Hegel's version, in the unavoidability of both self-determination's claim on us and the social institution and practices that embodied it. In the Kierkegaardian version, however, despair over something so absolute itself demands something extraordinary - a leap of faith - to ensure that it be achievable by us; and, in demanding the extraordinary, Kierkegaard was only setting the scene for the succeeding attempts at establishing the reality of freedom that, in turn, reached for the extraordinary... [that] somehow produces a satisfactory social whole capable of holding a collective allegiance to itself (361)."

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Certainty, historicity, faith and hope. It may be an ontogenetic recapitulation of phylogenetic understanding in my own thinking, but I find myself moving from certainly to historicity. I doubt if there ever was or will be a time when 2+2 does not equal 4, but it also seems essentially irrelevant. Not to the bookkeeping that necessarily accompanies a life, however figured, but irrelevant to that life itself as it is lived. Perhaps in placing faith in historic inevitability is just itself a step away from faith and hope, that once certainty yields, whatever replaces it must eventually and inevitably collapse into faith and hope.