question for philosophers (if this isn't your sort of thing, skip down)

In "The Moral Problem", Michael Smith at one point (page 10) says that, if we accept the Humean picture of moral psychology, "I should not think that the claim that people in circumstances like mine should give to famine relief is itself objective. For there is no reason to suppose that others could be brought to agree with me by means of a rational argument."

I haven't got far into the book yet, but the connection between objectivity and 'others being brought to agreement by rational argument' seems to be something the Smith thinks is right. And the connection here seems to be a claim that the possibility of people being brought to agree on a topic by means of 'rational argument' is necessary for claims about that topic to be objective.

Here's the question: should we understand this as meaning "solely by means of a rational argument" or just "in part by means of a rational argument"? If the former, then how is this not far too strong (e.g. Jeff is objectively taller than me, but that's not something argument alone could show)? If the latter, then how is this not so weak as to be inapplicable in the way Smith wants it to be (e.g. if we're allowed to pick desires to combine with rational arguments, then a Humean can say that agreement can be reached on any topic by means of rational argument)?

I really should stop fighting jet lag now and go to sleep.

Some pictures

At London's Heathrow airport, feeling kind of blurry and unsure where my next flight is.

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The view from my window.

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Me, arrived.

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The books that are supposed to last me 4 months.

Here we go

So, I made it to Berlin. After months of worrying about it. There was one point this morning, just before calling a car to get to the airport, when I felt like just not going. But the moment passed, and now I'm sitting on what seems like a pretty comfortable bed listening to some birds outside my window.

A few observations from the flight:

-The Americans and British hand out forms on the plane. The Germans don't. Getting through German customs took about 20 seconds. It kind of reminded me of going to France last year for a couple days, where the custom official didn't even look at me.

-Heathrow airport is quite a maze, but with glass walls. Kind of made me feel like a hamster in a hamster maze.

-British people all sound smart, but the guy sitting next to me had trouble figuring out which lightswitch belonged to him.

-'Maple Nut' is a new Cliff Bar flavor, and it's very good. A few extra grams of sugar, but well worth it.

-Michael Smith is a pretty good writer, but his objection to 'network' analysis of moral concepts doesn't seem too troubling - so what if some platitudes about rightness, badness etc. become too unspecific when all moral language is wiped out? There seem to be plenty of platitudes to go around, and there will be plenty of ones involving naturalistic stuff that can serve to avoid the permutation problem he describes. (Or maybe I missed the point, which is possible, since I was kind of busy thinking about my neighbor and his inability to find his own lightswitch.)

-I miss you all already. Why couldn't Germany just be in Jersey?