As I walk through cities nowadays I try to look through a Jane Jacobian lens at the diversity of enterprise and use about. By use, Jacobs literally means the uses buildings provide: living, working, commerce, diversion, to name some of the main ones. Nowadays it’s easy to take for granted mixed-use buildings, but they exist because the city planning orthodoxy of today – which Jacobs influenced through her writing and activism – makes space for them.

On a recent walk, I noticed how much was packed onto one side of a short city block on one of the lively stretches of East Hastings in East Vancouver. A gym offering luxury fight goods and apparel, a plant shop, a laundry service business, a kitchen renovation business, a small counterservice cafe offering “Italian street food”, a nail studio, a print shop, a beauty salon, a travel agency, an importer’s office, a Vietnamese restaurant, and a hip diner. Most of these on the ground level of a three-storey residential building occupying much of the block. On the corner past the diner a vacant lot recently bulldozed in preparation for a four-storey mixed-use residential building.

A fifteen minute walk away begins the vibrant stretch of Commercial Drive, one of the liveliest areas of East Vancouver. Near its northern tip is a niche example of mixed use. In a single one-storey building there is a secondhand clothing shop, a gift shop selling locally made crafts, a coworking space, and a gallery space. They are all run by a local art collective that uses the space to host events like stand up comedy nights and craft workshops. The types and variety of activities allow people to engage as passerbies, casuals, and regulars, enkindling friendship and community from repeated spontaneous interactions. This is one of the ways Jane Jacobs observes that diversity of use generates lively urban life.

Cities are unique in their routine ability to assemble groups of strangers spontaneously. And this intermingling of people is in turn what makes possible the variety and specificity of city life. Diversity is possible in cities, Jane Jacobs explains, because they bring together people in quantities so great that critical mass can be reached for projects and enterprises that wouldn’t survive in sparser and less diverse communities. Her book examines the ways that city planning can foster or thwart this diversity.