The Major Organ and the Minor Organs
Referring to the heart and the sensory organs, this term was used by Mencius to differentiate between men of virtue and petty men. Sensory organs such as the ears and eyes are called “minor organs” because they lack a capacity for thought and for cognition, and are hence easily directed by externalities when they come into contact with the latter. If a man were to only rely on his “minor organs,” he would be a captive of material desires and therefore become a petty man. The heart is the “major organ” which is naturally endowed with the capacity for thought and cognition. If a man is able to establish a dominant role for his “major organ,” then through the actions of his heart, he will be able to continually increase its inherent goodness and not have his judgment clouded by material desires, and thereby become a man of virtue.
Gongduzi asked, “We are all humans, so why are some men of virtue while others are petty men?” Mencius replied, “Those who follow their major organ become men of virtue, while those who follow their minor organs become petty men.” (Mencius)