I think that one aspect in which both Arthur and Odysseus differ in their conception of heroism lies in the difference between nobility and reality. Arthur embodies the essence of nobility. He views the world and its inhabitants in how it should be. He refuses to accept that others in the world could actually be evil, in part because he lacks this capacity for evil in his own sense of identity. Blindingly loyal, he learns from Merlin that war's only causation needs to be the prevention of further and future suffering. Arthur's heroism lies in how he represents an archetype of purity in nobility and honor. This is different than the heroism of Odysseus, which is rooted in practicality and a sense of guile. Arthur is heroic because he is unfailing in his honor, even when it comes at his own cost. Yet, it is difficult to envision anyone or anything taking advantage of Odysseus. The heroism in Odysseus is one of pure success and ensuring that situations and contexts result in a victory for himself. This sees Odysseus being pragmatic when he needs to be, careful and cautious at other times. Odysseus' heroism lies in his success, while Arthur's heroism is one in which his honor and sense of character is on display, with consequence and results coming a distant second at times.