If you're afraid to say your idea because you know (or suspect) that it's wrong, then you have already learned the hardest part of the lesson. Of course, it still remains to find out what the right idea is, but voicing one that you know to be wrong is hardly going to help with that.
I don't think this is quite right. Of course I don't know RM, but given PG's characterization of him, there's nothing to indicate that he never asks when he's unsure about something. PG only says that he never offers an opinion when he's unsure. I doubt that this interferes with learning. Saying something that's wrong to provoke a correction is not the only way to get the right answer. In fact I doubt that it's the best way, or even a good way . Many of us have learned the hard way that when someone says something wrong, they're not always interested in being corrected. Instead, if you want the right answer, you can always just ask, which doesn't involve being wrong, and makes it clear that you are ready to be instructed.
Knowing you're wrong is the threshold guardian to the adventure of hitting the mark correctly. I don't know how you embark on that journey without voicing it multiple times to multiple people.
“RTFM”
“Nobody’s going to do your homework for you”
“whathaveyoutried.com”