One of my pet ideas deals with the need to learn new things and the fact people do so, gradually incorporating what we've learned into a series of layers. One example: learning to drive.
I remember my long and difficult process of learning to drive (don't ask how many times I flunked the driving test). But gradually I became confident. Some 60 years later I barely notice how automatic some of my driving processes; I realize with a start that I did something now which would have terrified me years ago. We don't have children, so there's no one watching me drive who's going to absorb lessons from me, but that happens all around the world. People often make claims about the virtues or vices of drivers in different areas: "drivers here are aggressive and don't allow people to merge"--that sort of thing. I suspect part of this is people constructing narratives out of thin air, but a little bit might be the unconscious learning passed from parents to children on how to drive.
Another example: dialing the telephone. Kottke has a training film from the 1920's, training on how to use a dial phone. It's interesting, but what struck me was the instruction which serves as the title for this post. We don't think about it now, but when people made the transition from a telephone where you used a crank to ring the bell (remember "Ma Bell") to dialing numbers, they needed to be told the dash wasn't dialed. That knowledge rapidly sank into the culture, babies absorbing it with their mothers' milk, No one today needs to be told not to dial the dash.