Courage is resistance to fear,
mastery of fear–not absence of fear.
Except a creature be part coward
it is not a compliment to say it is brave;
it is merely a loose misapplication of the word.
Consider the flea!–incomparably the bravest
of all the creatures of God,
if ignorance of fear were courage.
Whether you are asleep or awake
he will attack you, caring nothing
for the fact that in bulk and strength you are
to him as are the massed armies of the earth
to a sucking child; he lives both day and night
and all days and nights in the very lap of peril
and the immediate presence of death,
and yet is no more afraid than is the man
who walks the streets of a city that was threatened
by an earthquake ten centuries before.
When we speak of Clive, Nelson, and Putnam
as men who “didn’t know what fear was,”
we ought always to add the flea–and
put him at the head of the procession.

— Mark Twain, “Pudd’nhead Wilson’s Calendar”