That's hard to say without more context.
Student or Learner
Please clarify the following in red. It's one sentence quote from Ralph Waldo Emerson.
Trust thyself: every heart vibrates to that iron string.
Please explain more easily. What does the "iron string" refer to, trust?
I know the essay. One thing, Emerson wrote in a sort of poetic way, so most of the things that you'll find written by him are not to be interpreted literally. I think he is trying to use a metaphor about "resonance". Our hearts resonate to that iron string, we are tuned with the same frequency as that string, with that string being whatever it is authentic. You will understand this if you refer to the first sentences of the essay, when he talks about some verses that he read or when he says "A man should learn to detect and watch that gleam of light which flashes across his mind from within".
That is my interpretation and I'm not a teacher.
"Then the iron string seems to refer to some sort of authentic inner voice or authentic self."