Why Did the Chicken Cross the Road?

Ptolemy: Someone will probably think of a simpler explanation in a few thousand years, but the present understanding is that the chicken crosses the road because it is constrained to move on this here sphere, which in turn has its center on this one over here. The end result is that, except in the rare case of retrograde chicken motion, the chicken does indeed cross the road. https://www.physics.harvard.edu/academics/undergrad/chickenroad