The very concept of a "master list" or, which is much more palatable for the anarchist within me, a broadly-defined series of literary corpora is one that many can accept at a theoretical level. There are, after all, certain works that a nation (defined here as a large cultural group that shares certain deep socio-cultural bonds in common and not as a synonym for a particular political organizing of peoples) very well might hold as being intrinsic for understanding that people: religious texts, political tracts, histories, epic poems and fictions. Things like Robert Burns' poetry being quoted in Scotland on Burns Night or recognizing who said "to be or not to be" or "behold I make all things new" are so familiar to certain cultures that one does not have to have been intimately familiar with the source material to understand the reference being made.
However, it is when we delve a bit further into the literary corpora that certain questions arise: Is this material suitable today, centuries after its composition? Are we neglecting other streams of thought by favoring this particular body of literature? An old truism, albeit one fraught with fallibility, is that history is written by the "winners." (In truth, histories are like any other power paradigm, with different expressions and strengths to those expressions.) Are non-majority groups (working class, women, non-whites, non-Christians) adequately represented, whatever might be meant by "adequately?"
These are questions that not only should not be avoided, but instead they should be embraced if one wants to set about constructing any sort of national literary corpus. I am the son of a retired high school English/literature teacher and I myself have taught literature and grammar in addition to social studies. As is common practice, there were the sets of five books that we were required to read (and later, to teach) for certain high school lit courses. Although I managed to avoid having teaching it, I remember questioning the validity of having John Knowles' A Separate Peace on the sophomore reading list when its setting (an all-white boarding school around the time of World War II) and characters were almost polar opposites of the experiences of the majority-black urban public school students I was teaching at the time. Although there are many elements to Knowles' story that recommend it to many sorts of readers, it would have been very difficult to present it as something vital, something important to readers who had become accustomed to not being represented at all (or even worse, in token fashion) in school reading curricula.
What does a teacher or literature professor do when confronted with this reality? After all, it isn't feasible to develop multiple, parallel reading lists or other literary canons in miniature without destroying the very concept of a national literary corpus. Yet the possible solutions are fraught with difficulties, which those who are opposed to the reimagination of the reading lists take glee in pointing out. How should we go about making the reading lists, and by extension, our understanding of what constitutes national "literary canon" more inclusive without seeming to "dilute" the quality of the literature or destroying even the shredded remnants of what formerly was a universally held understanding of what "all Americans should know?" (I use American literature here as an example as it is my native culture; similar arguments, albeit with different constituent works, would apply for other national literatures).
One solution, albeit not a perfect one (none are; we are a fractious species, after all) is to expand and to make the incorporation of diverse perspectives a foundational principle of understanding American culture and its literatures. By all means introduce students to the First and Second Great Awakenings and the Transcendentalist Movement. Just also introduce them to the writers of the Harlem Renaissance or the socialist writers of the late 19th and early 20th centuries. Have them question why certain writers outside dominant American literary circles utilized similar sources (the Bible, Shakespeare, the Declaration of Independence, the letters of Lincoln, etc.) to argue for radically different paths for American society in the fiction, poetry, and non-fiction of the past two centuries. By being aware of the similarity in sources as well as the divergences in interpretation and application, readers can be exposed to a wealth of different understandings of American history and literature in a way that shows the full truth of e pluribus unum without whitewashing the ideas or smothering dissenting views.
National literary corpora are not made to be static entities; they must be tested, tried, and occasionally discarded lest the national discourse become stale and enfeebled. Two centuries ago, a "well-read" American would be able to quote Thucydides and Horace in the original Greek and Latin. Today, while still esteemed by some, knowledge of either, in translation or in the original tongues, is not essential; their ideas, however, have been disseminated through others influenced by them. Sometimes, it is preferable for certain texts, or at least certain interpretations derived from them, to fall away and be cast in the dustbins of history. Surely few lament those execrable justifications for chattel slavery derived from Biblical passages!