Victor Hugo's quotation is one of my favorites. I believe he uses the bird as a metaphor for bravery, courage, and positive self-esteem.
Taken literally, the bird is not afraid to perch on the frail branch because it knows that if the branch breaks it will still be able to escape the danger by flying away. It has a song to be sung and, by God, it is going to sing it in spite of the precarious tree branch!
As a metaphor, you could use almost any situation to explain the meaning of the quotation. Let me use an extreme example to make my point:
Picture a brave mother who has learned she has terminal cancer. The mother has a choice to make; she can feel sorry for herself and try to hide from her family and the world OR she can go about her daily 'mothering' activities with the knowledge that she has the love and support of her family. In essence, she has chosen to be courageous, to live the remainder of her life in 'song' and positive self-esteem.
Here's where the metaphor gets really heavy, Vil! The mother 'knows she has wings' that will support her when death finally arrives. If she is a religious individual, the 'wings' will carry her to heaven. If she is not a religious person, her 'wings' will still carry her memory in the minds of those she has left behind! The 'song' she has sung throughout her lifetime will not be forgotten once she is gone.
The metaphor could also be used for soldiers, firefighters, policemen, and others who face danger and perilous situations. They can choose to ignore the 'frail branch' or they can choose to do their duty with the knowledge that a greater good will be the result of their efforts!
I hope this metaphor makes sense to you, Vil! It is a very powerful quotation!
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