In their book, Roman but Not Catholic, Kenneth Collins and Jerry Walls make the case that certain beliefs central to the Roman Catholic faith are unreasonable. This article evaluates, from the point of view of Eastern Orthodoxy, some of the arguments Collins and Walls make. In particular, it argues first that Collins and Walls are correct to criticize John Henry Newman’s theory of the development of doctrine as a reason to accept otherwise insufficiently supported Catholic doctrines. Secondly, it offers some (...) points of clarification concerning the matter of sacred tradition and attempts to show the areas of agreement and disagreement between Eastern Orthodoxy and the position that Collins and Walls articulate. Thirdly, it argues that Collins and Walls rely on what is, from an Eastern Orthodox point of view, a questionable view about the interpretation of scripture by assuming without good reason that the clear meaning of scripture is equivalent to the literal interpretation. (shrink)