A line from one of my 1997 columns - 'Do one thing every day that scares you' - is now widely attributed to Eleanor Roosevelt though I have yet to see any evidence that she ever said it and I don't believe she did. She said some things about fear but not that thing.
All species capable of grasping this fact manage better in the struggle for existence than those which rely upon their own strength alone: the wolf which hunts in a pack has a greater chance of survival than the lion which hunts alone.