Debug It!

Validate Your Diagnosis

We humans are multitalented creatures. Unfortunately, one of our talents is self-deception—we’re very good at convincing ourselves of something we want to be true. With that in mind, time spent validating that your diagnosis really stands up to scrutiny is time very well spent.

• Explain your diagnosis to someone else. They might spot a flaw, or the cardboard cutout effect might work its magic allowing you to do so.

• Check out a pristine copy of the source code, without any of the changes you’ve made along the way, and verify that your analysis still holds. You may have been careful not to introduce any unintended side effects, but nothing gives you more confidence that you succeeded than starting again from a known-good ...