Now you, this mathematician engineer, was the first one who could figure out actually doing flood controls on the Yellow River which made him the man and that legend has it is the first dynasty. How do we know it if it's a legend Mr. Hughes? We know it because the Shang Dynasty which ruled from 1532 BCE to about 1027 BCE actually wrote stuff down. How about that? A shout out to the Shang for writing stuff down. We know that because we have found what are called Oracle Bones and their religious beliefs took to them writing questions on these animal bones then they put a hot poker in it and crack it and read it. How about that?