384. Since all things of the mind have relation to the will and understanding, and all things of the body to the heart and lungs, there are in the head two brains, distinct from each other as will and understanding are distinct. The cerebellum is especially the organ of the will, and the cerebrum of the understanding. Likewise the heart and lungs in the body are distinct from the remaining parts there. They are separated by the diaphragm, and are enveloped by their own covering, called the pleura, and form that part of the body called the chest. In the other parts of the body, called members, organs, and viscera, there is a joining together of the two, and thus there are pairs; for instance, the arms, hands, loins, feet, eyes, and nostrils; and within the body the kidneys, ureters, and testicles; and the viscera which are not in pairs are divided into right and left. Moreover, the brain itself is divided into two hemispheres, the heart into two ventricles, and the lungs into two lobes; the right of all these having relation to the good of truth, and the left to the truth of good, or, what is the same, the right having relation to the good of love from which is the truth of wisdom, and the left having relation to the truth of wisdom which is from the good of love. And because the conjunction of good and truth is reciprocal, and by means of that conjunction the two become as it were one, therefore the pairs in man act together and conjointly in functions, motions, and senses.