That a person would lay down their life for another
is in your world the highest indication of selflessness and love.  So many of your heroes do so instantaneously,
without thinking, and people wonder at this. 
The reason is simple.  The
logical, rational mind thinks, and in this moment of pause, ego steps in.  Ego thinks itself separate and cares only for
self preservation.  Spirit knows it is
always safe, and that it cannot die. 
There is no need to think.  It
jumps in and serves the Whole, which is the same as serving the Self.  Selfless sacrifice would be better stated as
ego-less sacrifice for the Whole—a beautiful example of love in action.  Yes, praise your heroes, for their
instinctive actions demonstrate the true nature of All That Is—unity and love.