For every magical thing Steve Jobs revealed in his Apple keynote addresses, there were many other things he concealed. Like the devices he created, his life was more and more opaque even while becoming more and more celebrated. So his death this week came as a shock for nearly all of us, even though we knew that only grave illness could be keeping him from the company he co-founded and loved. He told us almost nothing about his prognosis—right through his last public appearance he was as turtleneck-clad and upbeat as ever. But suddenly, this week, he was gone.

Steve...