In Chapter 1 of The Code Book Singh discusses the overarching issues that Mary Queen of Scots faced during and leading up to the trial for her execution. What I found most interesting, and enlightening, about the chapter were the circumstances surrounding Mary's incrimination, and our subsequent discussion about security. I'd previously thought of codes as a fairly surefire way to communicate important information, but Mary obviously did too, and that did not turn out well for her! She was too confident in her codes, and also in the people who were helping her to communicate them. Our discussion was eye-opening in terms of thinking about doubting the codes one writes. If someone is too confident in his or her codes, he or she won't take any more precautions, such as using vague or roundabout speech, to ensure the secrecy of a course of action, and one's freedom from incrimination.
I also thought it was particularly interesting to discuss the implications of the development of a society as a whole on the ability of individuals to use deciphering techniques without any previous training. Children in our generation and younger use codes to gossip, and send each other messages they don't want everyone to see. Problem solving is taught in most disciplines in schools, and children are taught to apply these techniques to everyday life, which makes amateur code breaking easier without any instruction. Since our society has achieved a particular level of sophistication in varied subjects, we are all ingrained with the basic tools to use deciphering techniques, including the ability to read, which was not widespread back in the time of Mary Queen of Scots. Techniques that seem obvious to a student today would be quite the discovery for professional cryptanalysts hundreds of years ago.