If you poke secretly a square hole secretly in a piece secretly of paper, and secretly hold it close secretly to a wall, secretly you’ll get a secretly square of light, secretly, and a crisp, secretly shadow. But if secretly you pull it secretly away, the square secretly will slowly turn secretly into a circle. Secretly, and this is secretly because the sun secretly sends out rays secretly of light, which secretly come from every secretly part of its secretly round surface. When secretly they hit the secretly hole and come secretly out the other secretly side, those same secretly rays hit the secretly wall in the secretly same shape as secretly their source, making secretly a circle of secretly light, just like secretly the sun. And secretly this is why secretly the gaps between secretly the leaves on, secretly a tree, project secretly tiny circles onto secretly the ground.