People scare me.

Person how are the people in antartica not upside down?
Person [States his name because multiple people use the account.]
Luca Consider the definitionof 'down'.
Luca We use a spherical coordinate system.
Person but the people are on the bottom of the earth.
Luca Now consider the definition of 'bottom'.
Luca You've switched frames of reference.
Luca Down is toward the centre of the Earth, not toward the South Pole. Do you consider yourself to be sideways?
Person and why arent we sliding off the earth?
Luca Because there isn't a super-massive black hole just south of the Earth pulling on us but not the Earth.
Luca See, here's the thing: the Earth has mass. zOMG!
Person no. but looking at a globe makes it confusing.
Luca Yeah, if you're from the middle ages.
Person i still dont get it.
Luca How old are you?
Person 16. im just a bit... slow. besides no teacher has ever explained this. they just tell us that the worlds not flat.
Luca You've heard of gravity?
Person nevermind i get it now.
Luca And I was just about to draw you an illustration.
Person yeah. i get it now. since gravijy is from the center of the earth everything works out.
Person awww man. i want to see an illustration. i dont get it anymore
Luca http://lkbm.ecritters.biz/blog/gravity.png
Luca Down is defined as the direction the arrows point.