As the moments passed the yelps grew closer and louder. Again Buck knew them as things heard in that other world which persisted in his memory. He walked to the centre of the open space and listened. It was the call, the many noted call, sounding more luringly and compelling than ever before. And as never before, he was ready to obey. John Thornton was dead. The last tie was broken. Man and the claims of man no longer bound him.
– Jack London
The Call of the Wild, pg. 64