Architecture Professor Bill Mitchell loves cities. His romance with them began with a train, he says. Growing up about 200 miles inland from Melbourne, Australia, in “a lonely flyspeck” of a town called Horsham, Mitchell saw the train as the small town’s link to the city.

Horsham was a tiny town in the outback with a milkman, iceman, and a baker making deliveries from horse-drawn wagons. In the evenings, the train from Melbourne passed through town, the whistle signaling to Mitchell that another world existed beyond main street.

“The train is not only a train. It’s a symbolic connection to the big city,” says Mitchell, a professor of architecture and media arts and sciences and the director of the MIT Design Laboratory.

The train that cut through Mitchell’s hometown first introduced him to urban culture, he writes in his latest book, Placing Words: Symbols, Space and the City, a collection of essays he writes monthly for the Royal Institute of British Architects Journal. Mitchell’s essays are about the importance of thinking critically, and show his love for cities and urban culture.

Each essay uses architecture as a stepping off point, and encourages the reader to see many sides of an issue, or different levels of meaning in something. The train, for example, is transportation. But it is also a small town’s connection to another culture, a way for the people from both places to interact, and a means for a young boy to visit the city, fall in love with urban life, buildings, and design, and to find his calling. As an architect, Mitchell writes about how cities work, how buildings and people interact, and how buildings relate to each other.

Using specific examples — skyscrapers, drive-in movie theaters, a parking garage, or a farm stand — Mitchell writes provocatively about modern social issues to encourage discussion.

UBIQUITOUS COMMUNICATION

“Mostly (the essays) are concerned with cities, the flow of information through cities, the ways different kinds of places influence flows and interaction, and create meaning,” Mitchell says. In urban spaces today, architecture sets the scene for people to communicate both face-to-face and electronically at the same time, but the increased interaction and information flow are both good and bad, he says.

“The point is to understand it critically. Ubiquitous communication opens up all sorts of new possibilities to social interaction. At the same time, it opens up possibilities for greatly increased surveillance,” he says.

Mitchell’s goal in the book is to push people to look more closely at how things like technology — e-mail, instant messaging, and cellular telephones — change communication, for example, to see subtleties and complexities, he says.

“Instead of discussing issues at a level of grand abstraction, I try to take very concrete, very real, very meaningful situations and moments and try to draw out the layers,” Mitchell says. A train ride in Australia is one such situation.

FIRST TRIP TO BIG CITY

Mitchell was about 12 the first time he rode a train to Melbourne. It was Mitchell’s first encounter with a big city, and his family was attending the 1956 Olympic Games. Until then, Mitchell’s only sense of the city came when that train pulled into his hometown.

“The passengers dressed differently from the locals, and they talked of unfamiliar things,” Mitchell writes in “Carriage Return.” Passengers from Melbourne also brought with them newspapers, both serious broadsheets and scandalous tabloids. “News was scarce in the bush, in the days before portable radios and casual long-distance calls, so fresh papers were eagerly awaited; passengers would sometimes toss them out to the railway workers who stood leaning on their shovels as a train groaned slowly by.”

That train sparked Mitchell’s interest in cities and architecture, and eventually carried him to university and on a path that brought him to Cambridge, thousands of miles from that “lonely flyspeck” of Horsham. But today, as a man who spends much of his time in cities such as Boston and New York, he sees yet another level of meaning of that train.

“Decades later, it works in the opposite way,” he says. “Now, whenever I see an old steam train, I think of that small town.”