To read development narratives and zoning codes, one would think Boston was the Kowloon Walled City. New buildings must have maximum floor area ratios, minimum open space per unit requirements and at least one setback. Developers tout urban plazas and new master plans always show lots of new “green space.”

Too bad that, like modern art, it’s all bosh.

Leaving aside the theory, let’s look at the facts. Considering all the yards, setbacks and plazas that already exist, we can compare them to places supposedly lacking in open space.

In looking at Boston neighborhoods, it’s apparent that some of the worst areas of the City could be defined by open space and some of the best have almost none. The West End’s tower-in-a-park redevelopment has left it with loads of space and not much else. City Hall sits in what’s been called the largest back alley in the world and the streets created by urban renewal — Blossom, Staniford, Cambridge, New Chardon, Congress, Merrimac, Causeway, Nashua and Lomasney Way — are among the widest, most dangerous, most unpleasant and least walkable streets in the entire City. In contrast, the North End, Beacon Hill, Back Bay and the South End, with their narrow streets and closely-packed houses, are among the most beloved neighborhoods of Boston.

It’s not that they lack open spaces, but they have three key features overlooked by planners and developers: they relate to the street, they are defined and that they are places. A building relates to the street partially by being on it and partially by having entrances on it. One issue buildings since the end of World War Two have consistantly run into is that they occupy a city block, have a single entrance for pedestrians and sheer curtain walls at street level (except at the entrance to the parking garage and loading bays). This makes them fortress-like and deadens the street. A space is defined by the buildings around it, as opposed to the buildings being in it. Lastly a space is a place by virtue of it being designed for and used by people. For example, in Medieval Europe a square would have had a variety of uses — marketplace, public water supply, a space for religious or civic processions, an assembly space for citizens called up for military service and so on. It’s not a question of “programming” at all. A good public place won’t need to be programmed because the people will already be there.

Louisburg Square is Boston’s toniest address. There might be a few places with more valuable homes, but there are none more prestigious. It’s clearly defined by the rows of houses on all sides, the houses all interact with the streets and it’s a place where people go, if only to admire it or walk around it since the park has an iron fence around it.

Christian Science Plaza, by contrast, is all over the place. The buildings float in the space instead of defining it; they don’t interact with the street at all; and one would be hard pressed to find anyone there if it weren’t for the food trucks across from the Prudential Center (near the semicircle of trees). It doesn’t help that all the members of the church could probably fit inside the one in the picture with room to spare for the world’s remaining Samaritans, so the buildings are under-tenanted.

An open space in a city can be good, but planners and developers should not fall into the trap of assuming that all open space is good. There has to be a city for there to be public space in it.