"...I know they were enslaved, and then wiped out, by Frieza. That we're a warrior people. But I don't know much beyond that. Did we even have family units, for example? I know that becoming a super-saiyan was only a myth until Goku achieved it. What else did we believe? DID we have any beliefs?" It was hard to conceptualize everything he wanted to know in some ways. He knew it wasn't a pretty past--his Mother and Gohan had intimated that pretty strongly. But it was still part of him.