In reading a recent Financial Times article called, Are creative people the key to city regeneration?, I was reminded of a famous line from the late urbanist Jane Jacobs: “New ideas need old buildings.” What she meant by that is the following:

Cities need old buildings so badly it is probably impossible for vigorous streets and districts to grow without them…. for really new ideas of any kind—no matter how ultimately profitable or otherwise successful some of them might prove to be—there is no leeway for such chancy trial, error and experimentation in the high-overhead economy of new construction. Old ideas can sometimes use new buildings. New ideas must use old buildings.

And what she was effectively getting at is that we live in a world obsessed with historical data and precedence. To use the words of business thinker Roger Martin: “The enemy of innovation is the phrase ‘prove it.’” Because, if it’s never been done before, how can you prove it? You can certainly imagine it. But you can’t prove it.

If you’re in the business of building buildings, convincing your lender to give you the money to build something that’s never been done before, is an almost impossible sell. That’s not the way it works. Which is why Jane Jacobs famously said that “new ideas need old buildings.”

We’ve seen this story play out in countless cities around the world. The creatives move into an scuzzy neighborhood, make it cool and then investment follows. The neighborhood has been proven. But for this cycle to continue, we need a continuous stock of derelict buildings and undesirable neighborhoods, or at least areas that offer the same kind of affordability and flexibility to creative entrepreneurs.

Often these circumstances have been the result of failure. The proven ideas that got the buildings built in the first place became no longer relevant. And so the buildings were left to expire. But in many global cities, these kinds of areas are an endangered specifies. However, it’s in our best interest to make sure that we don’t lose our creativity alongside them.

Yesterday evening I met up with a talented Toronto-based technology entrepreneur who also happens to be passionate about cities. The conversation meandered between both worlds, but we ended up coming back to one central theme: It’s all about people.

Facebook didn’t just buy WhatsApp for the technology. It spent $19 billion on almost half a billion active users. That’s what matters. Do people want to occupy your (real or virtual) space? Have you created a community? Whether it’s an app, a building or a neighborhood, you’re useless without engaged participants.

And to be perfectly honest with you, that’s my ultimate goal for this blog. Ideally I’d like each and every post to inspire conversation and debate (just like this one did on gentrification). A one-sided conversation can only take you so far. The real value happens within communities.