The lithosphere is made out of solid rock, the mantle is a combination of solids and liquids, and the outer core is a liquid. the path of the seismic wave changes at the boundaries of each layer because

when they hit it at too shallow of an angle it causes them to curve away

emerging idea only occurs as a raw idea that could appear out of nowhere. meanwhile, to reach scientific consensus , that idea must be structured and tested over and over again through various experiments. the scientific consensus transforms the raw idea into idea that is more reliable through the process of scientific elimination.