The Earth is not flat. The Earth was formed by objects in space colliding, eventually they become so big that they gain gravity to pull things into its orbit. The more gravity, the more things get pulled into Earth's atmosphere, meaning that more objects in space kept colliding until the Earth gained so much gravity that it pulled its self into a spherical shape. Also, one of the rules for a planet to be considered a planet not a dwarf planet, is "It must be big enough to have enough gravity to force it into a SPHERICAL shape."
that is logic
