愚者千慮，必有一得

- A fool may give a wise man counsel.; A fool may put somewhat in a wise man's head.; A fool's bolt may sometimes hit the mark.; A stupid person may once in a while have a good idea.; Even a fool occasionally hits on a good idea.; Even fools sometimes speak to the purpose.; Once in a blue moon has a good idea.; The greatest fool, in a thousand schemes, must hit once on the truth.; There is chance that the foolish may hit on the truth by incessant endeavours.