Selection from Arcana Coelesita ~ Emanuel Swedenborg
It is to be known concerning the rational man in general that it is said to receive life, to be in the womb, and to be born, when the man begins to think that the evil and falsity in himself is that which contradicts and is opposed to truth and good, and still more is this the case when he wills to remove and subjugate this evil and falsity. Unless he can perceive and become sensible of this, he has no rational, however much he may imagine that he has. For the rational is the medium that unites the internal man with the external, and thereby perceives from the Lord what is going on in the external man, and reduces the external man to obedience, nay, elevates it from the corporeal and earthly things in which it immerses itself, and causes the man to be man, and to look to heaven to which he belongs by birth; and not, as do brute animals, solely to the earth in which he is merely a sojourner, still less to hell. These are the offices of the rational, and therefore a man cannot be said to have any rational unless he is such that he can think in this manner; and whether the rational is coming into existence is known from his life in his use or function.To reason against good and truth, while they are denied at heart, and only known by hearing about them, is not to have a rational, for many can do this who openly rush without any restraint into all wickedness. The only difference is that those who suppose that they have a rational and have it not, maintain a certain decorum in their discourse and act from a pretended honorableness, in which they are held by external bonds, such as fear of the law, of the loss of property, of honor, of reputation, and of life. If these bonds, which are external, were to be taken away, some of these men would rave more insanely than those who rush into wickedness without restraint, so that no one can be said to have a rational merely because he can reason. The fact is that those who have no rational usually discourse from the things of sense and of memory-knowledge much more skillfully than those who have it.
This is very clearly evident from evil spirits in the other life, who although accounted as being preeminently rational while they have lived in the body, yet when the external bonds which caused their decorum of discourse and their pretended honorableness of life are taken away, as is usual with all in the other life, they are more insane than those who in this world are openly so, for they rush into all wickedness without horror, fear, or shame. Not so those who while they lived in this world had been rational, for when the external bonds are taken away from them, they are still more sane, because they have had internal bonds - bonds of conscience - by which the Lord kept their thoughts bound to the laws of truth and good, which were their rational principles.
(from Arcana Coelestia 1944)
The genuine rational is from good, but comes forth [existit] from truth.• Good flows in by an internal way; but truth by an external way.
Good thus conjoins itself with truth in the rational, and they cause the rational to be. Unless the good therein is conjoined with truth, there is no rational; although there appears to be, because the man can reason (see above). This is the common way in which the rational is formed with man.
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The good itself of the rational, which is formed by the internal way, is the very ground; but truth is the seed which is to be sown in this ground. The genuine rational is never born in any other way. ...
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[G]ood itself flows into the natural through the rational, thus by an internal way, and enlightens the things which are therein; whereas truth itself inflows into the natural through the sensuous part, especially that of hearing and sight, and thus by an external way. Truth has its rise from this source, as may be known to everyone who reflects; but the conjunction of good and truth is not there, but is in the rational; therefore truth is called forth therefrom, thus out of the natural sphere into the spiritual; for the truth that is to be conjoined with good is spiritual.
(Excerpts from Arcana Coelestia 3030, 3098)
[Revisions by Ed.]