2 definitions
Definition.com
Inquiry (n.) looks impossible on the debater's argument: you cannot search for what you know, since you have it, nor for what you don't, since you wouldn't know what to look for.
Definition.com
Perplexity (n.) is the torpedo fish's sting: one touch from Socrates and both mind and tongue go numb, even in a man who has made a thousand fine speeches.