Full Idea
If I ask how things would be if Saul Kripke had come from no sperm and egg, but was brought by a stork, that makes sense. I create a context that makes my question make sense, which is a context that makes origin not to be essential.
Gist of Idea
I can ask questions which create a context in which origin ceases to be essential
Source
David Lewis (On the Plurality of Worlds [1986], 4.5)
Book Reference
Lewis,David: 'On the Plurality of Worlds' [Blackwell 2001], p.252
A Reaction
I'm not clear why delivery by a stork doesn't just count as a different origin, and hence it turns out to be essential to Kripke. If Kripke were a necessary being (and he's a good candidate), then he would have no origin.