When I write a complex legal brief, I must set forth the basic rules that apply to the issues under consideration.
Then I must apply the facts at hand to those issues, arguing that the facts more closely match law which favors my client, and not law which favors my opponent's client.
But even in the most elaborate briefs, both sides assume that courts decide cases based on precedent, that we have a system of common laws and statutes, and that a certain stylized procedure applies to the resolution of issues.
In "real life", though, we start from so many different assumptions, and we start from societal backgrounds which imbue us with so many cultural assumptions. A chance phrase can betray an unintended set of assumptions which the author either makes or keys into to make a point.
It's a problem of all communications--we are all prisoners of our own assumptions, but also of a stream of societal assumptions which we may not hold, but which we cannot speak without utilizing them. I do not believe that the solution to this is that odd academic "political correctness", which itself carries so much baggage that it is a largely unworkable mode of speech (the "anti-political-correctness" movement, if anything, is more laden with assumptions I reject). But I do go to sleep sometimes, conscious of something I wrote that might have been more precisely written, and avoided the baggage of an entire set of assumptions.