The objection above was "I sincerely have no idea why people believe so strongly that a human-level AI can build a superhuman AI. It is bizarre that this claim

The objection above was "I sincerely have no idea why people believe so strongly that a human-level AI can build a superhuman AI. It is bizarre that this claim is accepted with "little doubt" when there are very good reasons to doubt it: how on earth would such an AI even know it succeeded? How would it define the goal?" In response Yudkowsky is presented as a sort of superintelligent human with the answers, but of course we're back to the original problem, how do we know Yudowsky, who as far as I know does not make disprovable claims, is a superintelligent human with the answers? How would we define the goal?