Linking to Wikipedia articles and blog posts from other people is one of my favorite side effects of the design of the web. It's not just that it lets me learn new things myself - it also saves me lots of time explaining things to other people. Good documentation is a form of scripting, except it's for your brain - it's semi-automated information delivery. It's what allows us to move from the "sage on the stage" model of learning (where content delivery is tied to a person delivering it) to being able to spend more time exploring new things, new syntheses of ideas, and so forth because you're not spending all your effort getting the base data that's now become a commodity.
When ideas are modular and redistributable, they're easier to tweak, make, maintain, and generate, because an ecosystem created to be made of tiny bits is easier to add tiny bits to than an ecosystem created to be One Giant Thing. (Rephrased: modular systems make it easy to make modules.) And that gives you a lower barrier of entry into that ecosystem, whether those ideas are about software or music or metallurgy. And the lower the barrier of entry, the more likely people are to get into it while being able to do other things at the same time.
Think of it this way: people can do software as a hobby now. With open source, they can then bring that richness of their other world into the community of practice of software development and the things that support it. Can people do immunology research as a hobby right now? Chip design? Hearing aid manufacturing? (Why do you think there isn't much of a DIY culture around it, anyway?)
It's like there's a barrier. The Hobby Barrier. The cost has to drop - not just the equipment and materials cost, but the time cost and the social risk. This does not dumb things down. It doesn't make the art you're teaching need any less effort to master - it just makes it easier to work really, really hard and get there.
Andrew and I had this conversation over 4 years ago.
Me: “The question shouldn’t be ‘How do we make more engineers?’ It should be ‘How do we get more people to do engineering?’ How do we get people that aren’t necessarily engineers to do engineering things?”
Andrew: “It ought to be ‘How do we get engineers to enjoy engineering?”
Me: “Not just engineers, but everybody."
Huh, I should put this in my grad school application (it's from the same blog post as the bit above, but reworded to reflect the way my thinking's changed on how to teach things since).
October 2005, age 19: Give a man a leatherman. Tell him there are these things called fishing poles and nets, that he knows the stream better than you do, and can he help you figure out a way to pull this fishing thing off for his village.
December 2009, age 23: Tell the village that there are these things called fishing poles and nets; offer them any tools you can collectively find, and offer to introduce them to people from nearby villages who've made their own variants of fishing poles and nets before. Ask them to teach you about the river, because they know the river better than you do. Write down their stories so you can carry their words with you to share when you go back home. And stay in touch.