How to Disagree and always shooting the messenger

I love reading Paul Graham … I've read pretty much everything he has written and while I don’t always agree, I always come away from his articles with a new thought. In fact, I think he has most insightful blog/column out there.

 
Graham writes a new one entitled How to Disagree:

http://www.paulgraham.com/disagree.html

this is well worth reading. Many people have trouble disagreeing and the most common way to discredit an argument is to go after the messenger. Graham points out this is a really a poor argument as to why the messenger's point is bad.

but most humans give too much weight to the messenger and not enough weight to the message. That makes sense from a purely evolutionary point of view. If Stephen Hawking says something about physics, you might want to listen. But if Britney Spears starts discussing string theory, you might think she's talking about bikinis and not theoretical physics. This reasoning works most of the time as usually Hawking has interesting things to say about science and Spears is known for other talents.

But in politics and business, not listening to the messenger can lead to very bad decisions. Giving a little more weight to a new opinion of someone you like over those that you dislike makes sense. But a good decision maker should only weigh the messenger a little and focus much more on dissecting the message. The boy who cries wolf might be right sometime … you shouldn't just reject the message out of hand.