Weighing The Options

I received this in an email a few days ago (thank you, V) and it's had me thinking. It's a quotation from "Zen and the Art of Motorcycle Maintenance," by Robert Persig:

"If you have a high evaluation of yourself then your ability to recognize new facts is weakened. Your ego isolates you from the Quality of reality. When the facts show that you've just goofed, you're not as likely to admit it. When false information makes you look good, you're likely to believe it. On any mechanical repair job ego comes in for rough treatment. You're always being fooled, you're always making mistakes, and a mechanic who has a big ego to defend is at a terrific disadvantage."

And some more...

"If you know enough mechanics to think of them as a group, and your observations coincide with mine, I think you'll agree that mechanics tend to be rather modest and quiet. There are exceptions, but generally if they're not quiet and modest at first, the work seems to make them that way. And skeptical. Attentive, but skeptical. But not egoistic. There's no way to bullshit your way into looking good on a mechanical repair job, except with someone who doesn't know what you're doing."

Of course, I apply this to the field of health. For me, it's revealing how someone responds to new information (myself included). Do they embrace it forthrightly, test it, dismiss it? How much does where it comes from influence their response? How do they view the bearer of the news?

There have been some respectable doctors-turned-authors who I feel have painted themselves into a corner with their views.

• How does someone who endorses low-fat, vegan diets deal with those diets' apparent insufficiency of essential nutrients?
  
• How does someone who endorses low-carb diets deal with information about the beneficial role of intestinal bacteria and undigested starch?
  
• How does someone who endorses an aggressive supplement regimen deal with research questioning its lack of efficacy? Or safety?
  
• How does someone who endorses eating locally-grown food apply that concept to places that don't possess the resources to produce adequate food locally?

I'm not asking for answers to these questions. I'm just saying I learn about someone based on how they handle information that contradicts, or for that matter reinforces, their positions. (Still learning here myself.)
________Illustration of Right vs. Wrong from Current Configuration, where they argue for their position on the best method for hanging bathroom tissue.