"Approximately every fifty years, the accumulated wisdom and experience of an entire generation is wiped out."
Much of which philosophers call "tacit knowledge," which plays a significant role in the thinking of some economists as well:
However, we don't all turn into sages as we age. Three of my grandparents seemed like basically decent people, but I could tell even as a child that they didn't have much going for them. It never occurred to me while growing up that I could go to one of them for advice.