What has he learned?, W. muses. What are his four noble truths? He knows only that I am wrong, and that I have always been in the wrong. He's certain of that.
Could he, given such the indubitability of such a starting point, begin to reconstruct his sense of things, like Descartes? Could he, having reached such a realitatpunkt, begin building everything up again?
No. From the realitatpunkt of my stupidity, there's nothing to build, and nothing that can be built. The realitatpunkt must destroy everything.