The more Ryu learned about the three souls and seven spirits, the more he realized that the odds that he was the only one who knew about them was middling at best. He had run into too many of his abilities that would benefit from them to believe that he was the only one who could have figured all of this out. He was arrogant, but he wasn't foolish.
He wasn't the only one ever born with Mysteries of Heaven and Earth Pupils, if he had been, it wouldn't be ranked number one as the ranking was dependent on the feats of its past owners and the ties of Fate between them. He wasn't the first to form a Founding Dao and he most definitely wasn't the first to ever have an Origin Flame.
