I like the analogy. I never heard it before now, but I instantly understood what I think it meant: build something that is harder to live without. I have nothing to back this up but I’d think most people think of a vitamin as easier to live without than a painkiller.

> For example: was Facebook a painkiller? Hardly.

I don’t know. People without pain do take painkillers. And they can have a really hard time stopping. In that sense, I would argue that Facebook is a lot like a painkiller for a lot of people!