If I listen closely.. I can hear the sky falling too
The sky is falling is a saying which means the world is ending (made famous by the story of Henny Penny or Chicken Little, as it is commonly known), so Frank may be alluding to the fact that the world as we know currently know it, the social stigma behind being openly homosexual, may be changing. This is not only as a result of his letter, but also as people become more open minded. The listen closely is essentially frank saying that there are currently small signs of it and it hasn’t happened on a large scale yet.
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