What do you/they mean by "heart"?
From what I understand, heart can be read on different levels - from the heart of All being to, as I experience it, an area in the center of the chest near the physical heart. Others may read it differently. Mainly for me though it would speak of the essence of earth being beautiful, even though it may be appear to be forgotten more in some places/people than others at times. (yes, I can be forgetful for sure). It can also be an idea to read the poems of Rumi and see what, if anything, it does for each person.
edit : from a book on meditation from a different tradition
“Exercise : Exploring the inner heart
Perhaps you would like to try this. Close your eyes, and let your attention move gradually down toward the inner center behind the breastbone, a few inches to the right of the physical heart. You can start by focusing on the front of your breastbone, about eight finger-widths below the U-shaped bone at the base of your throat. Then, imagine a plumb line dropping from just behind your nostrils into the middle of the chest, behind this spot on the breastbone. Let the breath flow in and out to that spot. Feel and sense the energy there, in the inner body, behind the breastbone. Without judgment, notice how the energy feels there in the heart-center. It might feel soft or prickly, melting or hard. For now, let the inhalation flow from the nostrils down into the heart center, and flow back up from the heart before it passes out through the nostrils.”
also from a different book
“The ideograph for “heart” is a picture of a human heart: xin, . It means heart, mind, intention, center, core, intelligence, and soul all at once. The ideograph for beauty is mei, , meaning beautiful, satisfactory, good, or pleasing. It combines the sign for ram, , over a glyph, , that means big, vast, great, large, or high. Perhaps we might picture a flock of sheep in a pastoral setting as the symbol of beauty. In earlier times, however, older forms of the word showed a feathered headdress on a person. Beauty was a shaman crowned with feathers—someone dancing with all their heart.”
— The Way of Heart and Beauty: The Tao of Daily Life by Deng Ming-Dao