Readit NewsThis could be seen positively or negatively. One way of spinning it is that he was persistent in exploring ideas. Another way, though, is that something -- mythmaking, hype, his art, whatever it is -- has allowed history to ignore the fact that he seemed to have been wrong more often than he was right, along the lines of a broken clock being right twice a day.
In either case, I think there's something to be said for some kind of cultural and social context playing a strong role in how all of this is interpreted. A different person in the wrong place or wrong time might have been interpreted as a crackpot.
People like Leonardo and Newton are valuable thinkers because they once in a while produce a really good idea, and it doesn't really matter if they know themselves which ideas are good or bad. This is a really bad trait for a leader or a trader though.