Sun has been shining through the shutters of our south-facing flat's windows all morning, making ladder-like spotlights on the wood floor. The park was full of dogs and people: a body builder lifting what looked from afar like a giant, square piece of concrete, as if pulled up out of a London sidewalk; a young couple submerged and entangled in the grass; an office-attire wearing woman who spoke loudly to herself and a smartphone. The air smelled faintly of lemons and coffee.