Know your limits

Giberson on what experts should expound on, and what they shouldn't. Quoting his quote of someone criticizing the British Medical Association:

Why does the BMA think it knows anything about how we should live? It may know that if I live a particular way I'll become unhealthy, but why does it think that it can tell me that I should value my health more than my chosen way of life? What makes its members think that they are in any privileged position to answer questions like that?

Indeed.