Whereas a novel can describe a character’s unspoken thoughts, a play contains no such description. To overcome this limitation, a playwriter uses soliloquies. The character expresses his or her inner thoughts aloud, in the absence of other characters. Only the audience can hear what the character says.
A famous quote of MLK is: "Nonviolence is a powerful and just weapon. which cuts without wounding and ennobles the man who wields it. It is a sword that heals." This is why I believe that is the answer.
The author is saying that because of humans and the ways they are impacting earth is causing irreparable changes like causing animals to go extinct, etc.
