384. Since all the elements of the mind have to do with volition and discernment and all the elements of the body with the heart and lungs, there are two brains in our heads, as distinct from each other as volition and discernment. The cerebellum serves volition primarily, and the cerebrum serves discernment primarily. In the same way, heart and lungs are distinct from everything else in the body. They are marked off by the diaphragm and enclosed in their own membrane, the pleura, forming the region of the body known as the chest.

These two aspects are found united in other parts of the body, the ones called members, organs, and viscera; so they too occur in pairs--arms and hands, legs and feet, eyes, and nostrils, for example. Within the body there are the kidneys, the ureters, and the reproductive glands; and the viscera that are not paired are still divided between right and left. Further, the brain itself is divided into two hemispheres, the heart into two ventricles, and the lungs into two lobes. The right side has to do with the good that results from truth and the left to the truth that results from good; or in other words, the right refers to the good that love can do, which leads to the truth of wisdom, while the left refers to the truth of wisdom that results from the good that love can do. Since the union of what is good and what is true is reciprocal, and since they become a virtual single whole by virtue of that union, these pairs within us act together as a unit in our deeds, motions, and sensations.

50. Whenever the term spirit is applied to the Lord, it means His Divine life, thus the Lord Himself. This is clear from the following:

...He whom (the Father) has sent speaks the words of God. ...God does not give (Him) the Spirit by measure. The Father loves the Son, and has given all things into His hand. (John 3:34-35)

There shall come forth a Rod from the stem of Jesse.... The Spirit of Jehovah shall rest upon Him, the Spirit of wisdom and understanding, the Spirit of counsel and might.... (Isaiah 11:1-2)

I have put My Spirit upon Him; He will bring judgment to the nations. (Isaiah 42:1)

...he will come like a narrow stream; the Spirit of Jehovah will put a sign on him; then the Redeemer will come to Zion.... (Isaiah 59:19-20)

The Spirit of the Lord Jehovih is upon Me; ...Jehovah has anointed Me to preach the Gospel to the poor. (Isaiah 61:1, cf. Luke 4:18)

...Jesus, knowing in His spirit that they thought thus within themselves.... (Mark 2:8)

...Jesus rejoiced in (His) spirit and said.... (Luke 10:21)

...Jesus...was troubled in (His) spirit.... (John 13:21)

(Jesus,) sighing in (His) spirit.... (Mark 8:12)

[2] Spirit stands for Jehovah Himself, or the Lord:

God is a Spirit.... (John 4:24)

Who has directed the Spirit of Jehovah, or what man that of His counsel? (Isaiah 40:13)

(The Spirit of Jehovah) led them by the...hand of Moses.... (Isaiah 63:12, 14)

Where shall I go from Your Spirit? Or where shall I flee.... (Psalms 139:7)

(Jehovah said,) “Not by might..., but by My Spirit (he shall act).” (Zechariah 4:6)

They...provoked the Spirit of His holiness; therefore He turned against them as an enemy.... (Isaiah 63:10, cf. Psalms 106:33)

My Spirit shall not indict mankind forever, for they are flesh. (Genesis 6:3)

...I will not contend forever..., for the Spirit would fail before Me.... (Isaiah 57:16)

...blasphemy against the (Holy) Spirit will not be forgiven..., but whoever speaks a word against the Son of Man, it will be forgiven him. (Matthew 12:31-32, cf. Mark 3:28-30, Luke 12:10)

Blasphemy against the Holy Spirit is blasphemy against the Lord’s Divinity. But a word against the Son of man is something said against the Word, by interpreting its meaning wrongly. For the Son of man is the Lord in relation to the Word, as we have shown above.