Nice set of quotes with analysis.
It is interesting when Socrates says "The only thing I know is that I know nothing" as it is a Socratic Paradox. If a person says, "The only thing that I know is that I know nothing." What exactly does that mean (not metaphorically), literally? If the only thing they know is that they know nothing, then they know 1 thing. (in which case: nothing ≠ 1.) But looks like they are saying they don't know anything at all.
Simultaneously it is saying it is wise to know you do not know as knowing what you don't know teaches you what areas in your life you need to seek more information in. Knowing what you don't know gives you the opportunity to refer to someone else who can help you. Knowing what you don't know allows you to step back before making an ignorant and/or hasty decision.
Socratic Questioning is an interesting way to both elicit information and to make another see a point of view they may not have considered. An excellent example of this can be found here: http://www.socraticmethod.net/morality/page1.htm
I look forward to reading more from yourself soon.
Stay Golden,
Avi