6057. Before any statement can be made about influx and the operation of the soul into the body, it must be well understood that the internal man is formed according to the image of heaven, and the external man according to the image of the world; insomuch that the internal man is a heaven in the least form, and the external man is a world in the least form, thus is a microcosm. That the external man is an image of the world, may be seen from the external or bodily senses; for the ear is formed according to the whole nature of the modification of the air; the lungs according to the whole nature of its pressure, as also is the general surface of the body, which is held in its form by the circumpressure of the air; the eye is formed according to the whole nature of ether and of light; the tongue to the sense of the solvent and fluent parts in liquids; and, together with the lungs, the trachea, the larynx, the glottis, the fauces, and the lips, according to the power of suitably modifying the air, whence come articulate sounds, or words, and harmonious sounds; the nostrils are formed according to the sense of particles fluent in the atmosphere; the sense of touch, which encompasses the whole body, is according to the sense of the changes of state in the air, namely, to the sense of its cold and heat, and also to the sense of liquids and to that of weights. The interior viscera to which the aerial atmosphere cannot enter are held in connection and form by a more subtle air, which is called ether; not to mention that all the secrets of interior nature are inscribed upon and applied to the external man, such as all the secret things of mechanics, of physics, of chemistry, and of optics. From all this it is evident that universal nature has contributed to the conformation of the external of man; and hence it is that the ancients called man a microcosm.
 And just as the external man has been formed according to the image of all things of the world, so has the internal man been formed according to the image of all things of heaven, that is, according to the image of the celestial and spiritual things which proceed from the Lord and from which and in which is heaven. The celestial things there are all those which are of love to the Lord and of charity toward the neighbor; and the spiritual things there are all those of faith, which in themselves are so many and of such a nature that the tongue cannot possibly utter one millionth part of them. That the internal man has been formed according to the image of all these things, is strikingly shown in the angels, who when they appear before the internal sight (as they have appeared before mine), affect the inmosts by their mere presence; for love to the Lord and charity toward the neighbor pour out of them and penetrate, and the derivative things of faith shine forth from them and affect. By this and other proofs it has been made plain to me that as the internal man has been created to be an angel, he is a heaven in the least form.
 From all this it is now evident that in man the spiritual world is conjoined with the natural world, consequently that with him the spiritual world flows into the natural world in so vivid a manner that he can notice it, provided he pays attention. All this shows the nature of the interaction of the soul with the body, namely, that properly it is the communication of spiritual things which are of heaven, with natural things which are of the world, and that the communication is effected by means of influx, and is according to the conjunction. This communication which is effected by means of influx according to the conjunction is at this day unknown, for the reason that each and all things are attributed to nature, and nothing is known about what is spiritual, which at this day is so far set aside that when it is thought of it appears as nothing.