'Ah, I said, 'because the boy has a bicycle.'
'Not so fast, Watson. Think about it. Heidegger dies eight kilometers from the school. So the boy is moving very fast, because it is eight kilometers before a man on a bicycle can gat near him. And Heidegger dies because someone hits him very hard on the head. A boy can't do that, so there was someone with the boy - a man, let's say. But we looked very carefully at the mud all round poor Heidegger's body, Watson, and what did we find? Some cow tracks, but nothing more. No footprints from people, no bicycle tracks.