When you love someone enough, where in time does anything but the fact of the two of you ever pale to the rest of the world?

The homely, ungainly worm grows up and goes through metamorphosis, becoming a fully-matured butterfly, a common token of beauty. The devastating rain floods the world, but soon comes a breathtaking rainbow and everything is suddenly rectified.

"Love at first sight." Why is that phrase so compelling to us? Why is it redolent of such strong romantic sentiments?