Sarah

Sarah: "It represents knowledge... want me to explain?"
Photographer: "Of course."
Sarah: "As much as we try to know the only thing we know for sure is what is happening right now, and sometimes that is not even sure."
Photographer: "And as for the heart...?"
Sarah: "Well, the heart represents trust or faith in the unknown."

Heather

Heather: "I think it means longing for love."
Photographer: "In what way?"
Heather: "Well it's just trying to find true love."