《史记·三十世家·燕召公世家》
等到大禹年老时，又认为启不足以担当治理天下的重任，把君位传给了伯益。
及老，而以启人为不足任乎天下，传之于益。
When Emperor Yu grew old, he thought that Yi was not qualified to take up the great responsibility of governing the kingdom and passed the throne to Boyi. 