What does this quote mean from "Self- Reliance" by Ralph Waldo Emerson?Quote: Every heart is tuned to that string.

The quote seeks to embrace much of the Transcendentalist
philosophy of which Emerson was a part.  This movement sought to develop knowledge and
understanding within the individual.  At a time in American History, when industry and
commerce was taking a strong hold in America and individuals acted in concert with one
another in an almost conformist manner to make money, thinkers like Emerson sought to
bring back a sense of individual voice into this discussion.  For Emerson,
"Transcendentalism revolves around the self, specifically the betterment of the self." 
This was outside of the realm of religion or social acceptance.  The quote bring this
idea out.  In it, "that string" is the development of individual identity and hearing
one's "voice."  This is a pursuit that is individual, bringing out the idea that each
person holds a certain uniqueness that is different from all
others.