Why was her diary secret? Well, because she wanted it so. And that should be enough. When it comes to information that any given person regards as intimate about oneself, that should always be enough. It doesn't matter that someone else might peruse that information and say, "there is nothing special here." Why? Because it is not that person's judgment to make. There may be nothing special about my exact bank balance…
You are misinterpreting the post. Derek isn't claiming that your decisions about what to keep private shouldn't be respected, but rather that you - the person who wishes to keep things private - might benefit from thinking twice about what is it you are actually afraid of, and whether it is all rational. Claiming that her diary was secret because "she wanted to" is really beside the point. People constantly "want" ma…
In this case, Derek and his friend appear to want something which is harmful to them (almost completely transparency in all their activities, to the extent of revealing a private diary on request). People are just pointing out why this is harmful, and why he should think twice before proclaiming that 'secrets are just facts'.
You can't ever take back having released a lot of information into the public domain - for example a diary would reveal your location on almost every day of your life - very useful to catch you out on some technicality on tax or some other issue. People are already (in my opinion) giving out too much info, sometimes deliberately (Facebook), sometimes without their knowledge (Tempora).
I actually agree with his point about code and ideas (that it's better to share than not), but think it is completely wrongheaded and downright dangerous to extend that as far as a private diary of thoughts and events.
Derek isn't claiming that your decisions about what to keep private shouldn't be respected, but rather that you - the person who wishes to keep things private - might benefit from thinking twice about what is it you are actually afraid of, and whether it is all rational.
It is completely rational to believe that a growing lack of privacy is a serious problem in our society, and would undermine our freedom from government or corporate interference and manipulation on every level of our lives. You don't have to look far for examples of gross misuse of personal data.