Out in the world
Gravity hill
At places like this one in Canada, a car left out of gear seems to roll uphill. Does it?
No: the road really goes downhill.
Why? The road really goes downhill. With no level horizon in sight and slopes all around, your brain gets wrong which way is down.
Picture: Laurie Piskun, CC BY-SA 3.0 · Wikipedia(opens in a new tab)