"Doubt is the key to knowledge" (Persian Proverb)
Perception is how we see things and doubt is a key element in perception. When we see something we don't necessary need to believe it, it depends on how we perceive it that make us believe something immediately or have doubts about it. When we doubt something we have this tendecy to try and get the correct answer and therefore we acquire more knowledge.
1. A cultural example could be that not all cultures believe in God. Some cultures perceive God as a superior being but they don't call it God. Some cultures have doubts about God's existence and they all have different ways and paths to search for this "truth".
2.In school sometimes teachers make mistakes and most of the time they are not corrected and we end up learning something that is not correct. But sometimes some one notices the teacher's mistake and doubts that what he/she said is correct, so he asks and then the correct answer is given and knowledge is acquired thanks to the student's doubt.
3. One time, I was in my math class with Mr. McDowell and he was solving an equation on the board but for some reason I doubted that the answer was correct, something didn't look right. So then I started solving the equation on my own, and I figured what he did wrong and I corrected him. Thanks to my doubt everybody was corrected and acquired the real knowledge, thanks to the way I perceived the problem.