There are a couple different theories, but the oldest instance of the symbol can be traced back to ancient Rome. It appeared on coins from the Roman colony of Cyrene, mimicking the seed of an ancient plant called silphium. This plant was crucial to the Cyrene economy and was said to have medicinal properties.Additionally, in those days the silphium seed was used as a form of contraceptive, and thus became associated with love and intercourse.So, according to this theory, the shape wasn’t even supposed to represent a heart at first—thanks to autopsies, Romans were well aware of what the anatomical heart looked like. Over time, the heart came to be associated with depictions of silphium seeds because both were already separately associated with love.Another theory holds that the symbo