"Much like the wind propels a sailboat’s motion, light is sailing the winds of spacetime"

Our 4D world is all about spheres and perceptions.
Quantum mechanics and Art are proving it.

And while all's relative, one thing we can hold absolute:
marveling at this beautiful world and feeling lucky to have this complicated, yet simple thing, called Life.

http://nautil.us/issue/46/balance/what-this-drawing-taught-me-about-four_dimensional-spacetime