Most, if not all film folk will tell you that books and films are two different media, often much to the chagrin of the original author. Books are most generally individual efforts (with the guidance of editors), while film is a collaborative effort with the vision of the director usually predominant.

Sometimes a film follows the book quite closely; the westerns WARLOCK and THE OX-BOW INCIDENT are exemplars.

But how closely do films like IN OLD ARIZONA or EAST OF EDEN follow the original. In the first case, the scenario follows the plot quite well, except the protagonist, The Cisco Kid is changed in the movie from O. Henry's Gringo (Caucasian) badman to a Mexican badman, and the Kid has remained Mexican ever since...and became a good guy in the process. Perhaps the creators of In Old Arizona, felt that since the main character had a Mexican sounding nickname, he ought be portrayed that way..

In the Elia Kazan film of Steinbeck's novel, the changes were even more stark. The film only covers the last third of the generational story. The Bible thumping, cold, autocratic father played on film by Raymond Massey, in the book is actually a rather sympathetic, loving father. But Kazan wanted to tell a somewhat different story than Steinbeck wrote. Both are powerful, but they are not the same. The TV mini-series was closer to the scope of EAST OF EDEN, but not nearly as compelling screen entertainment, in my opinion.

So it all boils down to this, I think. One needs to accept each form of media on it's own merits. I believe it doesn't matter whether the Wayne or the Bridges TRUE GRIT is truer to the source novel, but which is better as a movie on its own merits. I have no opinion on that, as I haven't seen Beau's brother Jeff's version.