I have been bonked all afternoon. It’s that time of year. Brooklyn’s stoops, plumped by great pumpkins, are bright with autumn leaves. Sweeping up means braving the barrage of falling kernels, hurtling down as if pelted by malicious squirrels. Like ideas, most won’t germinate. My head hurts. The Linux kernel was the slingshot stone pelted against the Goliath of Microsoft Windows. It’s a neat reminder of the cyclical nature of commercial innovation that the extraordinary boy-innovator William H. Gates III would face potential disruption from a (minority) Swedish-speaking Finn...