The three pairs of terms

click on images for full-size:

Contemporary bank building in Santa Fe, built in the required adobe style

The Colosseum in Rome, with a restored section

My three pairs of terms -- complex and simplified places, thick and thin places, dense and diluted places -- are not equivalent. A place can be complex without being thick, dense without being complex, simplified without being thin, and so on. But it is true that density and thickness will encourage complexity, and thinness and dilution often accompany simplification.

Thickness or thinness describe the substance of the individual roles rather than their multiplicity and interactions. Thinness happens as social roles become less substantial and more abstract. This is a separate issue from how complex a place is, since the place could still be complex if it contained multiple thin roles interacting in intricate ways.

There can be absolutely diluted places, where what traces history has left have no grammatical bearing at all on the texture of contemporary action. There cannot, however, be absolutely thin places, whose social roles have no substance whatever. Even the thinnest of economic roles -- supermarket shopper, ticket vendor -- cannot be isolated from the complexities of their constitutive contexts, connections, and meanings.