It depends what you're talking about. One could be asking questions. One could be proposing hypotheses and exploring the kinds of experiments that might discover new knowledge. One could be imagining, daydreaming or creating something new, where the process of manifestation will require trial and error.
There are times when we don't know what we don't know. For instance, it's very common for someone who's been on a horse a few times to say "yes, I can ride" and think they're telling the truth. They'll talk enthusiastically about the times they cantered or galloped etc. What they don't know is that they can't ride at all. The horse took them for a ride; they were not in control of the animal; it was simply following a lead horse and rider by training and habit. In any other situation, that person is unable to read or predict the horse's behavior, control speed or direction, sit or post at the trot, or ride without showing daylight between bum and saddle. He or she is also likely to be at risk of a serious accident. We could portray or ridicule such a person as a "clown" - many have - as in the movie of Maime. But it's a sadistic kind of humor to take the piss out of and shame someone because of their ignorance.
