I saw the sentence on the TED videoed lecture delivered by Ms. David. This is the link: https://www.youtube.com/watch?v=NDQ1Mi5I4rg&feature=youtu.be
"What he showed me is that courage is not an absence of fear,"
said the lecturer, and at 15:40 comes the sentence:
"Courage is fear walking."
I am not sure what walk means here. Does it mean the same as Oxford Dictionary's sixth entry as (literary) (of a ghost) to appear? Or, does it mean fear walks on foot in a metaphorical way? (Then what does it compare to if it is the case...like walking away, or walking with the person?)