Robinson Crusoe is at its core a story of adventure , and true to its nature the hero must rely upon his wits and courage to survive .Defoe goes to extraordinary lengths to tell how Crusoe sorts through the goods on the wrecked ship to find just what he needs to survive and how he builds his rafts to bring it all ashore .He demonstrates self reliance in building his plantation in Brazil .Throughout the novel one could see this theme in action .