The World as a System On June 27, 2008, the man who erected Microsoft walked out of its headquarters for the last time as a full- time hand. workers lined the hallways, réclame and clapping, some holding banners that read “ Thank you, Bill. ” He smiled, gestured, tried to look relaxed but the moment was emotional. For thirty- three times, he’d lived and breathed this place. Every wall, every line of law, every product launch — his fingerprints were on all of it. Now he was leaving to attack commodity much bigger the world’s hardest problems.