In the story ‘The Things They carried’ , Tim O’Brien describes courage as being “like an inheritance, and by being frugal and letting it earn interest , we steadily increase our moral capital in preparation for that day when the account must be drawn down.”
I think that Tim believes courage to be something like money almost, he uses words like ‘interest’ and ‘frugal’ to get the point across that courage isn’t something that you can just do. You have to wait for a good moment, it takes a lot for a person to actually be courageous and their is always gonna be opportunities to have courage, but that also gives you many more opportunities to be a coward.
I would define courage as being strong willed because it takes a lot to have courage. I once heard someone compare courage to a diamond, he said “Courage is like the diamond very brilliant; not changed by fire, capable of high polish, but except for the purpose of cutting hard bodies, useless.”