KESTENBAUM: Spreadsheets have left us in a different world, though. It’s a world where we are constantly asking what if. And by we, I mean not just accountants and people on Wall Street. Like, all of us – me more than I would like. It’s gone way beyond spreadsheets. It’s like, what if I flew Thursday instead of Friday? What if I took 78 instead of Route 280? Where is traffic better? What if I stopped exercising? What if I ate more vegetables?