The 4th chp in Roger Olson, Reformed and Always Reforming, is about the influence of postmodernity and postfoundationalism on postconservatives. The chps sweeps through many ideas with names and quotations, but I can only give a sampling here and I ask this question:

Is is possible, in this age, not to acknowledge the legitimacy of some of these ideas?
He begins with the standard view: pomo is skepticism about grand narratives so that everything is local and particular. Some pomo folks, hard postmodernity, is deconstructive as it unmasks the power behind truth claims.
The softer kind — that which is picked up in some, if not most, postconservatives — is that all truth claims emerge from a narrative context. And here’s a very important point, and one that the critics of both emerging and postconservatism fail to appreciate and opt instead for a bludgeoning instrument:
“knowledge may be relative even if truth is not” (127). “This is not relativism but recognition of the relativity of perspective inherent in all human thinking.” “Truth may be objective, but knowledge never is.”
Everything about postconservatism flows out of this conviction.
Olson speaks about the Evangelical enlightenment that bought into the foundationalist thinking of Descartes and the Enlightenment, and he points to Strong and Hodge and Carl Henry.
Olson points to Stan Grenz and John Franke (Beyond Foundationalism) as an example of evangelicals who are postfoundationalist. I would add to this now John Franke’s book The Character of Theology.
Rodney Clapp, too: “evangelicals need to acknowledge that all their truth claims are contestable and that their confidence lies in the power of the Spirit and in faith rather than in some neutral and objective rationality divorced from the Christian perspective” (133).
The alternative?
1. Proper confidence instead of foundationalism.
2. Perspectival nature of all human knowledge.
3. Critical realism.
True truth is out there; but our knowledge and claims are value-shaped.