In this section Keller pits Foucault against C. S. Lewis. He presents Foucault’s case as being that any declaration of truth is actually a power play, and that truth is entirely relative. He quotes C. S. Lewis’s objection to to this, which is that Foucault’s premise is itself a declaration of truth, so it would work against itself. C. S. Lewis also makes the analogy of a window, saying that you see through a window, like Foucault claims you can see through a declaration of truth, but that this is only useful if there is something to see behind the window. If everything is a window, then there is nothing to see.
I think I agree with Keller in this particular case. Not all declarations of truth are power plays and not all statements of fact are equally valid.
I think this boils down to the question, does reality exist? Is there an objective truth, a right answer. I think there is. This is one of the few assumptions required to be a rational materialist. As an assumption, I cannot logically prove it. However, I think science’s track record of correct predictions provides decent evidence.
So I agree with Keller on this one. I have a caveat to mention, though, and that is to distinguish between Truth and truth. Capital ‘T’ Truth gets used in a lot of strange ways, but I understand it to mean the absolute, immutable, 100% true state of things. Basically, the way the universe really is. I believe such a thing exists, but I do not believe it is knowable. We can use the scientific method to approach it, and sometimes we describe the best of our efforts in that regard as lowercase ‘t’ truth, but we cannot fully understand Truth. Anyone who claims to know Truth, especially on extremely complex subjects as human behavior, is not believing in the same sort of thing as me. Keller in this section does not seem to be presenting anything problematic in this regard, but I want to address it now to avoid confusion if the various “truths” are conflated.