Lucretius

Next, I maintain that mind and spirit are interconnected and compose between them a single substance. But what I may call the head and the dominant force in the whole body is that guiding principle which we term mind or intellect. This is firmly lodge in the mid-region of the breast. Here is the place where fear and alarm pulsate. He is felt the caressing touch of joy. Here, then, is the seat of intellect and mind. The rest of the vital sprit, diffused throughout the body, obeys the mind and moves under its direction and impulse. The mind by itself experiences thought and joy of its own at a time when nothing moves either the body or the spirit. p.70