Agreed. This comes back to the need for a common understanding of what being an agreeable human being involves. "Common sense" etiquette doesn't work because, in my opinion, there is no such thing as common sense.
On the other hand, I'd probably think you were a bit of a dick if you tried to tell me what being an agreeable human being is.
Edit: This comment was...less than coherent. What I'm getting at is that I agree with you, and that I think the core of being "not an asshole" is understanding that other people are just like you in regard to their being far from perfect. The guy that just cut you off in traffic may have terrible hemorrhoids, be angry about something at work, or perhaps just heard that his daughter died. You never know what other people are going through.
On the other hand, I'd probably think you were a bit of a dick if you tried to tell me what being an agreeable human being is.
Edit: This comment was...less than coherent. What I'm getting at is that I agree with you, and that I think the core of being "not an asshole" is understanding that other people are just like you in regard to their being far from perfect. The guy that just cut you off in traffic may have terrible hemorrhoids, be angry about something at work, or perhaps just heard that his daughter died. You never know what other people are going through.