Faith
We all tend to hold our personal beliefs close, and we defend them fiercely in the face of detractors. We know that, however ridiculous they might seem on the surface, they play an important part in making us who we are. These intensely personal views give us strength of character and form the basis by which we make our decisions. I am, of course, referring to cold remedies/prevention. Seriously, people really have deeply held beliefs about how to avoid or treat a cold, and they will preach their cure as devoutly as any missionary. My problem with these cures is that it's not possible for me to know how things would have gone without their echinacea and zinc cookies; it would take a large controlled study to evaluate their effectiveness. Over the years I have tried zinc lozenges, nasal rinses, vitamins, and herbal supplements. And I'm not saying they don't work. What I am saying is that I'm lazy, and I'm going to get better eventually regardless.