Protagoras

This is an early morning revelation, and probably requires further thought given that I was struggling to differentiate Protagoras and Procopius(!), but it seems to me that the solipsistic utterance 'man is the measure of all things' is more meaningful with the caveat 'that man claims to apprehend'. It suddenly struck me that Heidegger must have been talking about something, no matter how obscurely, and I think thatwas the distinction between what is (concreta) and what is, or can be, perceived and manipulated within our cognitive frame (abstracta). It seems to me that the whole thrust of ordinary language philosophy and it's 'evil twin', semantic holism, is that we need to be careful to distinguish between the two. There is what is, or 'the facts' as Wittgenstein put it, and how we interpret what is through our fallible interface. Perhaps this is what Heidegger was trying to examine. Something for me to consider more closely. I know that my personality inclines me to construct complete models of a reality to which I can be no more than a biased observer. I wonder if is the totality of Heidegger's realisation?