It's a funny thing about lists, isn't it? Regardless of the category, it's human nature to want to be at the top of whatever it is being listed. So it was last week when an international cost-of-living survey, published Monday, ranked Tokyo as once again the world's most expensive city, ahead of Moscow, Osaka and last year's priciest metropolis, Hong Kong.

Tokyoites probably felt as proud as they did rueful on hearing this dubious news. Why? Because as ordinary -- that is to say, shallow and competitive -- human beings, they figure there must be some distinction attached to being named the "most" anything. And if the category happens to be "most expensive," well, what's so bad about that? Doesn't it summon up images of the bubble-era capital, all glitter, neon and champagne, when the Japanese economy seemed set on an unstoppable course toward World No. 1? If it does, it resembles the bubble in this respect, too: It's an illusion.

The boring truth is that the list reflects only a narrowly defined slice of reality. The biannual survey of 144 cities, conducted by Mercer Human Resource Consulting, doesn't really look at those places from the viewpoint of their native residents. It is tailored primarily to the requirements of governments and international corporations setting expatriate cost-of-living allowances. Consequently, while the rankings are based on cost comparisons in some 200 categories, not all of the categories are defined in ways that would mean much to locals.