What did the old gringo confess to Harriet about his past?

The old gringo goes on to tell Harriet how sanctimonious he was, being judgmental of other people's foibles and shortcomings. He muses about mortality, his own and others, and what it all means at the very end. Harriet tries to comfort him, but she can tell he is lost in his memories. He tells her that it is only now that he realizes how Hearst used him to sell newspapers and that the truth had been manipulated in the editing process. They each are quiet and say that they will talk again tomorrow, knowing that they may not live long enough to have that conversation.