Lots of rotten news coming from South Africa these days. Allegations of corruption swirl around President Zuma’s entourage. The union federation demands an investigation of the leader of the ANC youth wing. Judges are issuing writs and newspapers are writing scare headlines.The news is worrying bad — the corruption seems to be real and if anything getting worse. But it is also reassuring: despite occasional lunges toward clampdowns on the court system and the free press, these vital institutions of democracy are still in good health.