India, July 31 -- For millions of years, we lived on this planet but left no trace we were here.

Tools changed that, and cave art. Then came architecture. Built habitation remains our stamp upon the world; a signature of who we are.

It's not a great scrawl, the one we've been using in recent centuries. Modern architecture's biggest flaws are well-documented: blocky templates replicated over and over, with little thought for local traditions and contexts; price as the greatest determiner, leaving homes and schools, malls and offices darker and dingier than they needed to be; every sq ft capitalised on, leaving open spaces and green cover shrinking in cities.

Now, the urban-density and climate crisis offer a chance to hit reset.

"Cities...