There’s an expression in politics that one campaigns in poetry but must ultimately govern in prose. That is to say, words and lofty ideas are easily generated, but making a society that actually works in practice is the hard part.

Soaring rhetoric about the destiny of a people or a nation must necessarily give way to nuts-and-bolts pragmatism that collects the garbage, keeps water, traffic and sewage flowing, and lets citizens go about their everyday lives with a reasonable balance of freedom and security.

The same might be said of architecture — that one designs in poetry but must build in prose. This is particularly true when an abstract cultural or aesthetic philosophy encounters the gritty realities of construction, the limitations of materials and finite budgets, and the “mundane” needs of the building’s occupants. This encounter between abstraction and everyday living lies at the heart of “The New Modern House: Redefining Functionalism” by Jonathan Bell and Ellie Stathaki.

While the book’s tone and subject matter tend at first toward the academic, its focus ultimately bends more toward the 50 actual homes the authors have chosen as examples of this new functionalism. Their gripe isn’t with modernism per se, but rather how somewhere along the way the movement got hijacked by self-proclaimed sophisticates, practitioners who indulged what Bell and Stathaki call a “superficial fascination with novelty.”

Architects and designers aiming for innovation or improvement is a given and a good, but if they single-mindedly pursue abstract notions about pure forms or spaces, they risk severing the necessary connection to everyday life.

That rift, the authors contend, is where modernism went wrong, and the ease with which digital technology can be used to create virtual (but sometimes un-buildable) designs has only made things worse. Both make the process and the product seem antiseptic and effortless, and they encourage editing of untidy elements that might muddy the aesthetic waters with the grime of actual life.

Domestic architecture, they insist, is “the realm of things, a constructed space specific to individual lives.” Mass, line, texture -- all good things to include, as long as you don’t forget things such as comfort, sunshine and the fact that sometimes people have to go to the bathroom.

Bell and Stathaki do not argue for functional utility only, or for clinging to traditional elements of residential design out of habit or nostalgia. The simplicity and directness of modernism is fine, but homes are not just machines for living. They are “experiential” places, capable of evoking moods and atmosphere and all of the visceral responses that humans associate with shelter. And they have to serve people of all stripes, not just the wealthy or some theoretical “no kids, no pets, no mess” crowd that seems the intended audience for the starker examples of modernist houses.

Make your way through this heady introductory discussion and you land at the book’s simple center, a compilation of international “case studies” that looks at three environments for the new modernist home:

Rural — Just as some modernist design elements are iconic, so are some modernist settings, though you might not think of open countryside as one of them. But barns, grain silos and chicken coops are great examples of a no-frills approach to building design. Unfortunately, the open landscape context has for decades been linked to the exclusivity of modernist home design, because it suggested only well-heeled clientele with the means to afford trendy architects and plenty of well-situated land. Some of the homes featured here do enjoy spectacular settings, but most are not particularly upscale.

Suburban — Here, the concern is avoiding the convention and conformity common to suburban developments. The featured homes employ “common” materials such as wood-plank siding, metal roofing and gray concrete block, but just as many bolder choices — walls of loose rock held captive in rectangular wire mesh “blocks,” corrugated fiberglass and compressed-straw panels that create super-insulated walls. One home contains steel and concrete recycled from Boston’s Big Dig roadway project.

Urban — Urban settings can involve a host of challenges, from small infill lots, sloped or terraced terrain, and the historical context of surrounding homes and neighborhoods. Brick, steel and glass are favorite materials, not surprisingly, and many of these homes must pack a good deal of efficiency into a modest amount of square footage.

The diverse lineup of home designs, materials, and settings makes for an informative and interesting read, but one of the book’s best features is its added focus on the process of architecture and the adventures of some owner/builders.

In addition to the usual images of finished homes, the reader sees rough concept sketches, crude mockups, highly detailed scale models and in-progress construction photos for many of the featured homes. These serve as additional reminders of the physical reality of our shelters, and of the lives we spend in and with them.