What logic leads Socrates to the conclusion that human wisdom is worthless? What are two fundamental ideas that back up his reasoning?

For Socrates, an unexamined life is not worth living, yet Socrates finds the examined life to lead to the discovery that he has no wisdom. At the same time, the oracle of Delphi has declared Socrates to be the wisest man. To disprove the oracle, he searches for he who must be wiser than himself, as Socrates believes he has no wisdom, and yet, finds that it is those who think they are the most knowledgeable and wise who are indeed the most ignorant. Therefore, wisdom -- as expertise on matters of being human -- is only held by those who have not done enough examining to see their (true) ignorance, and thus the worthlessness of wisdom. If chasing wisdom is what makes a life both examined and worthwhile, then without the chase (which requires not having already achieved or grasped wisdom) there is no worth.