Traditionally, we have always regarded the son who does not know how to ask questions as either very young, or as less developed even than the simple son. But perhaps he is not actually a blank slate. Perhaps he is actually the son who is so sure of his own opinions and so set in his own worldview, that he is unable to disentangle himself from those views and subject them to rational questioning and debate. 

haggadah Section: -- Four Children
Source: Rabbi Baruch Boudilovsky