Critics in a certain mood too often resemble armchair outfielders nit-picking Ty Cobb. They style themselves as giant-killers. The will to batter this or that sacred cow becomes primary. Logic flies out the window. Such is the case with Joseph Millichap's erratic appraisal of Nobel laureate John Steinbeck.
Mr. Millichap makes the valid point that Steinbeck was welcomed and affected significantly by Hollywood - ''the most often and most successfully adapted of all our major writers,'' he writes. And Millichap's richly researched stories of various productions have historical value. But since he is essentially a film critic, Millichap gets in over his head when he attempts to evaluate the books as literature rather than as the material of adaptation.
The critic's thesis is deeply negative. He claims that, dating from the publication of ''Cannery Row'' in 1945, Steinbeck committed artistic suicide: ''When he abandoned the realistic and documentary modes for a sentimental and meretricious imitation of the silver screen, film began to have an adverse and eventually fatal influence on his fiction.''
Millichap's quest for vitriol brings to bear no body of critical observation to support his attack. When he undermines ''East of Eden,'' for example, he asks our belief simply because it's he who calls the novel ''corny.'' And he merely paraphrases Steinbeck's editors at Viking as having warned against certain shortcomings in the finished work. Where are the footnotes providing quotes and dates?
Millichap appears to have a love-hate relationship with Steinbeck. Ambivalent emotions can produce contradictions, and Millichap further courts the loss of credibility by giving full play to certain conflictive positions.