There’s a term used in medicine called “the pertinent negative” that helps doctors and other medical professionals diagnose illnesses and identify problems. Essentially, it’s to look for what’s missing.

For example, a pertinent negative is when it appears someone has heart failure but they haven’t gained weight, a common symptom of heart failure. To a doctor that’s weird, and it’s a pertinent negative, because weight gain is missing from the symptom list.… Read the rest