While the biographies by the Gelbs and Louis Sheaffer are standard references in regard to the dramatist, I am spending some time of late paging through Travis Bogard and Jackson R. Bryer’s edition of the Selected Letters of Eugene O’Neill, some of which may come as a surprise to those familiar with the picture of O’Neill in those biographies or in the otherwise informative Ric Burns PBS documentary of 2006. Instead of the brooding, taciturn poet, O’Neill is an often cheerful, garrulous figure, complaining about his taxes and his children (expressing pride in the latter too), joking, reminiscing, and plotting his next career moves aloud as craftsman and artist; one letter expresses his delight at the idea of being parodied by radio comedian Jack Benny. And because O’Neill wrote very little for publication about his own work, it is in these letters that he has the most to say about drama and the theatre as he approached it. In one of his more extended comments about tragedy, he wrote on 19 June 1931:
As for Aristotle’s “purging,” I think it is time we purged his purging out of modern criticism, candidly speaking! What modern audience was ever purged by pity and terror by witnessing a Greek tragedy or what modern mind by reading one? It can’t be done! We are too far away, we are in a world of different values! As [Oswald] Spengler points out, their art had an entirely different life-impulse and life-belief than ours. We can admire while we pretend to understand — but our understanding is always a pretense! And Greek criticism is as remote from us as the art it criticizes. What we need is a definition of Modern and not Classical Tragedy by which to guide our judgments. If we had Gods or a God, if we had a Faith, if we had some healing subterfuge by which to conquer Death, then the Aristotelian criterion might apply in part to our Tragedy. But our tragedy is just that we have only ourselves, that there is nothing to be purged into except a belief in the guts of man, good or evil, who faces unflinchingly the black mystery of his own soul! 
The recipient of this letter was New York Times critic Brooks Atkinson — which will likely make the Village Voice‘s Alexis Soloski cringe. Not only did O’Neill maintain friendships with several critics of the period, including Atkinson and George Jean Nathan, he went much farther than that, soliciting advice from these critics about his new plays before they were even finished, let alone before they went into rehearsal. Two months later, O’Neill responded to Atkinson’s extended criticisms of Mourning Becomes Electra, the manuscript of which he had submitted to Atkinson for his thoughts:
And criticism which might open one’s eyes to muzzy spots and be of real service never comes until after the opening when, for better or worse, it’s all over. That’s one of many reasons why I’m always glad to have any critic (whose opinions I respect, and whose right to criticize the drama I admit) read my scripts before the openings. Unfortunately producers violently object to this. They want a surprise value at all costs. Also, between us, they know their acting and directing usually are judged better if the critic knows nothing of the play they are supposed (in most cases so mistakenly!) to interpret! 
For the current New York Times‘ first-stringer’s response to early-period O’Neill, click here and scroll down.
Of course, O’Neill was an exceptional dramatist, and Atkinson an exceptional critic. But the theatre, drama, and criticism evolve and change not because of the common run of dramatists and critics, but because of these exceptions.