3. Provide multiple pieces of evidence when possible. Many essays have a point to make and make it, relying on a single piece of evidence from the text or beyond the text, for example a critical, historical, or biographical source, in the hope that it will be enough to make the point convincing. Clive Staples Lewis. HarperCollins, 1998 - Fiction - Upon its first publication, The Screwtape Letters was immediately recognized as a milestone in the history of popular theology and has since sold more than a quarter of a million editions. Now superbly reconditioned and rebranded as part of the Signature Classics range. Screw letters. CS Lewis. Harper Collins, - Religion - In this humorous and insightful exchange between two devils, CS Lewis examines moral questions about good versus evil, temptation, repentance, and grace. Through this wonderful tale, the reader emerges with a better understanding of who he is,