Her blog “Brain Pickings” ranges across the past and present, the arts and sciences, steering her cohort to unexpected delights. In our conversation at the Brooklyn Historical Society, she talked about a nineteenth century astronomer, a twentieth century elm tree, and a twenty-first century blight: people who walk down the street staring at their devices. But why does it vex her? It’s not as if she wanted to strike up a conversation with a passing stranger. Because, she said, “it creates an atmosphere of isolation.” Debatable. And we did, in the most amiable way. With music from Gregorio Uribe.