From Douglas Adams, author of Hitchhiker's Guide to the Galaxy:

1. 1. Anything this is in the world when you're born is normal and ordinary and is just a natural part of the way the world works.
   2. Anything that's invented you're between fifteen and thirty-five is new and exciting and revolutionary and you can probably get a career in it.
   3. Anything invented after you're 35 is against the natural order of things.