I think you've taken this discussion to a whole new level Bill. The original idea of this thread is that "weight should not be a consideration for backpacking, so just get out and hike with whatever you have." I've responded to this already, with my argument (and others) that there are circumstances where weight necessarily is a factor for some people, depending on their situation.

I'm interested in your idea of defining "ultralight" backpacking as carrying only what is essential. I agree in principle, but I still think it's not going to serve as a one size fits all philosophy. And I don't think it's just about the differences in the trip.

Last year I worked our gear list down to what we believed was "bare essentials." Of course, on a group hike, agreeing on what is "essential" is a matter of compromise. But we did pretty well to cut out a lot of weight. Unfortunately, my shoulders still hurt at the end of the day, which is why I keep looking at other areas to cut (short of spending a lot of money on new gear).

But if a person narrows down a bare essentials list to the one you outlined, it still skirts the issue of the weight of those "essentials." My essentials, building on what I already own, are pretty heavy. I still hike with them, carrying most of the weight of my son's gear as well, and I still have fun. But I know if I wasn't physically capable of carrying this much weight I'd have to start looking at spending money on the big three, for a start.

I know I still carry items that I would consider non-essential, which is where the idea of trade-offs that Daisy mentioned come into play. But I don't think I could really consider myself even a light backpacker if I stuck to a list of essentials, based on the gear I have. My gear serves me well, and I like what I have, but I see advantages to having lighter gear.

Personally, if we're talking about definitions of "ultralight," I propose the following questions:

1. Does the weight of my pack cause me physical pain?
2. Do I limit my trips because of the weight of my pack?
3. Do I have to leave my pack behind to explore anything off the planned route?
4. Do I obsess about the weight of my pack?

I guess if a hiker could answer NO to all of these questions, I don't see why they are any worse off than anyone who considers themselves an "ultralight" backpacker because of some high-tech gear list (no offense Glenn). It's a little more involved than just a list of bare "essentials," but I do think that's a good start.