Anatomy class and Manhattan voodoo, my nightmare's bad dream manifested in real life October. Skulls in the windows and pull apart hearts in the doorway. The four chambers, each one filled with pumping blood. The atrium, the aorta and the ventricles. One part of the heart receives blood from the body and pumps it into the lungs, the other does the polar opposite, moving blood from the lungs to the body. Your body is smarter than you, extremely intelligent without the use of verbal communication. If you take the time to understand the way your body works, maybe, just maybe, you can gain the courage to treat it right so it works like the magical machine it was intended to be.
If you don't listen to it, you're naive and only really working against yourself.