Galen was right about many things, but wrong in a huge number also. He never actually dissected a human body, but made estimates based on his dissections of animals primarily monkey, assuming that they would be very similar if not identical to the human body. This was folly, as he even stated that the chin was constructed of two bones, when it is quite clearly one. Galen wrote in his writings that the human body was perfect in every way, and as such suggesting that God constructed a perfect being, and the church liked this a lot. With support from the church, Galen could write anything he wanted and the people would believe it, as if the church said something, it must have been true.