Edit. Totally screwed the joke up.
If a princess kisses a frog and it turns into a prince, that's a fairytale.
If she leaves the frog alone for billions and billions of years and it just happens to become a prince, that's science.
If a princess kisses a frog and it turns into a prince, that's a fairytale.
If she leaves the frog alone for billions and billions of years and it just happens to become a prince, that's science.