He says that the Spinal cord is part of the brain, but I say that the Spinal cord and the brain are two different units connected that make up the CNS (Central Nervous System).
See, the Spinal cord is connected to the Medulla Oblongata by the Occipital bone (which is where the Spinal cord starts). The brain ends at the medulla oblongata (the lower half of the brain stem).
It's like a plug and a socket. They are not one, but two that connect.