THE orthodoxy of the Middle Ages looked upon angels and devils and departed human spirits as being personal invisible entities. They personified the powers of good and of evil, and made of them caricatures and monsters that flitted from place to place, attempting to subjugate the souls of men or to bring them within their power.
The governmental institutions during those times were those of oligarchy, and the poor were dependent on the favours of the rich. The power of the Church was supreme, and the dictates of the clergy suffered no disobedience. Servility and the craving for personal favours were the order of the day, and this state of mind necessarily influenced and modified the religious conceptions of the people.
The Supreme Spirit of the Universe became degraded in their eyes to a personal tyrant, into whose favour they attempted to wheedle themselves by penitences, supplications, and by means of the intercessions of priests, who were supposed to be his favourites. Everything that could not be reconciled with existing prejudices and opinions was attributed to the devil; and the horrors of the inquisitions, religious persecutions, and witch-trials are too well known to require to be recalled to the memory of the reader.
"Pneuma" or "soul," means a semi-material spirit, an essence or form which is neither "material," in the common acceptation of this term, nor pure spirit. It is (like everything else in the universe) a form of will, and may be with or without any intelligence. Usually it means the connecting link between spirit and body; but there are beings who belong entirely to the realm of the soul and have no such bodies as are commonly called "material."
It may be said that the soul is a certain state of activity of the will, and the same may be said of the physical body; for if we look at the universe as being a manifestation of will in motion, then all forms and objects that we know of, or which we can imagine, are certain vibrations of will.
Thus we may look upon physical nature as being constituted of a low order of vibrations; upon the soul as a higher octave of the same, and of spirit as one higher still. If the physical body dies, the lower octave ceases to sound; but the higher one continues and will continue to vibrate as long as it is in contact with the highest; but if the spirit has become separated from it, it will sooner or later cease its activity.
Thus if man dies the soul remains, and its higher essences go to form the substance of the body of the paradisiacal man, "the man of the new Olympus", [chapter 4] and the lower essences of the soul, from which the spirit has departed, dissolve in the astral elements to which they belong, as the earthly body dissolves in the elements of the earth.
This dissolution, however, does not take place immediately at the time of the separation of the soul from the body, but may require a long time. That which constituted the mind of a man will still continue to exist after the death of the body, although it is not the man itself.
"If a man has been true during his life, his spirit will be true after the man's death. If he has been a great astronomer, a magician, or alchemist, his spirit will still be the same, and we may learn a great many things from such spirits; they being the substance of the mind which once constituted the terrestrial Man." (Philos., Tract v.)
There are two deaths or two separations: the separation of the spirit and soul from the body and the separation of the spirit from the astral soul, or, to express it more correctly, of the spiritual soul from the merely intellectual and animal soul. If a person dies a natural death (i.e., from old age), his passions having died out during his life, his selfish will having become weak and his mind like that of a child, putting its confidence in his father, his spirit and soul will, at the time of his death, become free from material bonds and be attracted to the body of Christ.
[1. Boehme says: "When the soul has passed through death, it is then in the essence of God. It remains with the works which it has produced here, and in this state it will behold the majesty of God and see the angels face to face. In the unfathomable world where the soul is, there is no end or object which that soul would have to attain. Where the carrion is, there will the eagles assemble." (All that the soul desires will come to it.) Forty Questions, xxi. 3.]
"Such a soul is herself the flesh and blood of Christ, and Christ is her Master. She does not enter into communication with mortals, because she has no desire for anything earthly. She does not 'think' or speculate about terrestrial things, nor worry herself about her relatives or friends. She lives in a state of pure feeling, bliss, and enjoyment." 
[2. Boehme says: "The majority of souls depart from their terrestrial forms without the body of Christ (divine love), but being connected therewith only by a small thread." Such souls, having but little spirituality, will not exist in such glorious bliss as those whose spirituality has been unfolded upon the earth and who loved God above all.]
Such is the fate of those who die a natural death in God; but the conditions of those who die prematurely without being regenerated, either by their own hands or in consequence of some accident, differ greatly; because, although their souls have become forcibly separated from their bodies, the spirit does not therefore necessarily leave the soul, but remains with it until another separation takes place.
They remain in such cases human beings like any others; only with this difference, that they do not possess a physical body, and they remain in such a state until the time arrives when, according to the law of Nature and their own predestination (Karma), their physical death should have taken place. At that time the separation of their higher and lower principles takes place.
Up to that time they possess their astral bodies. Such bodies are invisible to us, but they are visible to them, and have sensation and perceptive faculties,  and they perform in their thoughts that which they have been in the habit of performing during life, and believe that they are performing it physically.
[3. Sensation is an attribute of life. If life resides in the astral body, the astral body will have sensation, and as long as that body is connected sympathetically with the dead physical body, it may even feel any injury inflicted upon the latter. The physical body, if it is inanimate, has no sensation; the latter belongs to the inner man. Wherever the centre of consciousness is established, there is sensation.]
They still remain in the earth sphere, and Paracelsus calls them Caballi, Lemures, &c. They are still in full possession of their earthly desires and passions: they attempt to satisfy them, and are instinctively attracted to persons in whom they find corresponding desires and passions, and to such places where they may hope to satisfy them, by entering into sympathy with such persons (mediums), and they are therefore often inclined to instigate such mediumistic persons to the commission of crimes and immoralities; neither can they avoid doing so, because, by losing their physical bodies, they have lost the necessary amount of energy and will-power to exercise self-control and to employ their reasoning faculties.
They often haunt the places where they used to spend their time during life,  thus attempting to find relief from their burning thirst after the gratification of their desires. Wherever their thoughts attract them, there they will go.
[4. Books might be filled with reliable accounts of obsessions, of haunted houses, and instances in which such ghosts have been seen are exceedingly numerous. Some persons, that may not be able to see them, may feel them instinctively, or even physically, like a cold wind, or like a current of electricity passing through the body. (see "Borderland" * )]
* Hartmann, Franz. "Vampires" in quarterly review Borderland (London), 3, 3 (July 1896). Leadbeater, Charles W. The Astral Plane: Its Scenery Inhabitants, and Phenomena. London: Theosophical Publishing House, 1915. 183 pp.
If they have committed some crime, they will be bound by repentance to that place where it was perpetrated; if they have a treasure buried, care for their money will hold them there; hatred, or desire for revenge, will tie them to their enemies;  passion turns them into vampires, and connects them with the object of their passion, provided that there are some elements in these objects which will attract them; because the astral body of an evil person cannot influence the mind of a pure person, neither during life nor after death, unless they are mutually connected by some similarity in their psychic organisations.
[5. Chinamen and Hindus have been known to kill themselves for the purpose of revenge, so that their soul may cling to their enemies and trouble their minds or drive them to suicide. It is also well proven that wars are often followed by numerous suicides occurring in the victorious army.]
[6. Such a case of vampirism is personally known to me. A young man killed himself on account of his passion for a married lady. The latter loved him, but did not encourage his advances on account of her matrimonial obligations. After his death his astral form became attracted to her, and as she was of a mediumistic temperament, he found the necessary conditions to become partly materialised and trouble her every night. It required a long-continued effort until she finally became rid of the Incubus. If our practitioners of medicine were better acquainted with occult laws, many "mysterious” cases that come under their observation might become clear to them, and they would obtain a deeper insight into some causes of mania, hysteria, hallucination, &c.]
"Under certain circumstances, such human entities will become visible or manifest their presence in some manner. They may appear in bodily shape, or remain invisible and produce sounds and noises -- such as knocks, laughing, whistling, sneezing, howling, groaning, sighing, walking, trampling, throwing stones, and moving articles of furniture or other objects, and all this may be done by them for the purpose of calling the attention of the living, so that they will obtain an opportunity to enter into communication with them." 
[7. Fragment, "De Animabus Mortuorum." A great part of this fragment has been lost. All such spirits are the products of imagination and will. If a person has an evil imagination he creates a corresponding form in his mind, and if he infuses that form with his will he has then created a "spirit," which will attract similar influences.]
But not all the appearances of supermundane or submundane visitors are caused by the apparitions of the ghosts or astral bodies of suicides or victims of accidents, nor by the astral corpses and the Evestra of the dead; but there are other invisible entities sometimes haunting the houses of mortals, and becoming occasionally visible and tangible to the physical senses, if the conditions necessary for such a purpose exist.
"One of these classes is made up of beings called 'phantasmata.' These ghost-like beings are 'nocturnal spirits' having reasoning capacities similar to those of man. They seek to attach themselves to men, especially to such as have very little power of self-control, and over whom they can gain power. There are a great many kinds of such spirits, good as well as evil ones, and they love to be near man. In this they are comparable to dogs, who are also fond of the company of men. But man can profit nothing from their company. They are empty shadows (shells), and are only an encumbrance to him. They are afraid of red corals, as dogs are afraid of a whip; but the brown corals attract them."  (Herbarius Theophrasti: De Corallis)
[8. Paracelsus recommends the wearing of red corals as a remedy against melancholy. They are said to be ruled by the influence of the sun, while those of brown colour are under the influence of the moon. The red ones are disagreeable not only to Phantasmata, but also to Monsters, Incubi, Succubi, and other evil spirits; but the brown corals are agreeable to and attract them. I know of some cases of melancholy, depression of mind, hypochondria, &c., that have been successfully treated by the wearing of red corals, while other articles employed for the same purpose had no effect, and the cure could therefore not be attributed merely to the belief of the patient The ignorant will find it easier to ridicule such things than to explain them.]
"Some people believe that such spirits can be driven away with holy water and by the burning of incense; but a genuine holy water cannot be had so long as no man is found who is holy enough to be able to invest water with an occult holy power, and the odour of incense may sooner attract evil spirits than drive them away; because evil spirits are attracted by things that are attractive to the senses, and if we wish to drive them away it would be more reasonable to employ disagreeable odours for such a purpose."
"The true and effective power against all evil spirits is the spiritual will. If we love the source of all good with all our heart, mind, and desire, we may be sure never to fall into the power of evil; but priestly ceremonies -- the sprinkling of water, the burning of incense, and the singing of incantations -- are the inventions of clerical vanity, and they therefore take their origin from the source of all evil. Ceremonies have been instituted originally to give an external form to an internal act; but where the internal power to perform such acts does not exist, a ceremony will be of no avail except to attract such spirits as may love to mock at our foolishness." (Philosophia Occulto)
Another class consists of the Incubi and Succubi, of which rabbinical traditions speak in an allegorical manner as having been created by the spilling of the seed of Adam (the animal man) while engaged with Lilith, [Wikipedia] his first wife (meaning a morbid imagination). Paracelsus says in his book, De Origine Morborum Invisibilium, lib. iii: "Imagination  is the cause of Incubi and Succubi and fluidic Larvae. The Incubi are male and the Succubi female beings. They are the outgrowths of an intense and lewd imagination of men or women, and after they take form they are carried away. They are formed of the sperma found in the imagination of those who commit the unnatural sin of Onan in thought and desire."
[9. The word "imagination" ought not to be mistaken for empty fancy; it means the power of the mind to form into a substantial image the influences which are actually present.]
"Coming as it does from the imagination alone, it is no true sperma, but only a corrupted salt (essence). Only a seed that enters the organs which Nature provided for its development can grow into a body. If seed is not planted into the proper soil it will rot. If sperma does not come into the proper matrix it will not produce anything good, but something useless. Therefore the Incubi and Succubi grown out of corrupted seed, without the natural order of things, are evil and useless; and Thomas of Aquinas has made an error by mistaking such a useless thing for a complete one."
[10. It is here not the question of merely visible and tangible things, but of the products of the mind, which are also substantial, and which may become visible and tangible under certain conditions. "The invisible body as well as the terrestrial body act each in its own way. That which the visible body performs is done with its hands; the inner man works by means of his imagination and will. The works of the former appear to us real; those of the latter like shadows." (Morb. Invisib., iii.)]
"This sperma, coming from the imagination, is born in Amor Hereos. This means a kind of love in which a man may imagine a woman, or a woman a man, to perform the connubial act with the image created in the sphere of the mind. From this act results the expulsion of an ethereal fluid, impotent to generate a child, but capable of bringing Larvae into existence."
"Such an imagination is the mother of a luxurious unchastity, which, if continued, renders man impotent and woman sterile, because much of the true creative and formative power is lost by the frequent exercise of such a morbid imagination. This is frequently the cause of moles, abortions, miscarriages, and malformations. Such corrupted sperma may be taken away by spirits that wander about at night, and who will carry it to a place where they may hatch it out. There are spirits that will perform an 'act' with it, as may also be done by witches, and, in consequence of that act, many curious monsters of horrible shapes come into existence" (De Orig. Morb. Invis.).
"If such monsters are born from a powerful, conscious imagination, consciousness will also be created in them. The spirits of night can use all that is born from such sperma according to their pleasure, but they can use nothing of a human character or possessing true spirit."
"Amor hereos is a state of the invisible body, and is caused by an overheated imagination, stimulated to such an extent as to eject sperma, out of which Incubi and Succubi grow. In ordinary pollutionibus nocturnalis, the body loses sperma without any effort of the imagination, and the spirits of night can therefore not use it for their purposes."
"If women have passed beyond the age of fertility and are unchaste and of a vivid imagination, they often call such things into existence. If persons of either sex have lewd desires and an active imagination, or if they are passionately in love with another person of the opposite sex, and unable to obtain the object of their desire and fancy, then an Incubus or Succubus may take the place of the absent object, and in this way sorcerers call Succubi, and witches Incubi, into existence." 
[11. Mediaeval occult literature and that of Modern Spiritualism contain many examples of Incubi and Succubi, some having appeared visibly and tangibly; others, though unseen, were touched and felt. Such cases are at the present day much more numerous than is commonly believed, but they can only "materialise" if the necessary conditions are given. They are therefore only felt during a state of sickness, and after the recovery of the patient they disappear, because they cannot draw the elements necessary for materialisation out of a healthy constitution. Such Incubi and Succubi are the products of a physically and morally diseased state. The morbid imagination creates an image, the will of the person objectifies it, and the nerve aura can render it substantial to sight and touch. Moreover, having once been created, they attract to themselves corresponding influences from the astral soul of the world.]
"To prevent such unfortunate occurrences, it is necessary to be chaste, honest, and pure, in thought and desire, and whoever is unable to remain so should not remain single. Imagination is a great power, and if the world knew what strange things can be produced by the power of the imagination, the public authorities would cause all idle persons to go to work and to employ their time in some useful manner, and they would take care of those who are unable to control their own imagination, in order that such evil results should be avoided." (Morb. Invis, iv.)
[12. Animal instincts cannot be suppressed, and the "flesh" cannot be "mortified," except by awakening a higher psychical activity in the place of the lower ones, or by an exaltation of the spiritual nature over the animal principle in man. Abstinence in acts is useless for spiritual development, unless it is followed by abstinence in thought. Enforced celibacy does not make a priest; a true priest is a saint, and saints are persons who have outgrown their carnal desires.]
"The so-called 'Dragon' is an invisible being, which may become visible and appear in a human form and cohabit with witches. This is accomplished by means of the sperma which is lost by masturbators, fornicators, and prostitutes in acte venereo  and which such spirits use as a corpus to obtain for themselves a human form, because the whole of the human form is typified in the sperma, and if such spirits use the sperma of a certain person, it is as if one man puts on the coat of another man; and then they have the form of that person and resemble him in all his parts and details."  (De Fertilitate, Tract, ii.)
[13. This is the kind of "spirit" created by the followers of P. B. Randolph, according to the instructions given in his book called "Eulis." [Archive.Org] ]
[14. They cannot, however, become visible, unless they can draw some of the astral essence from the person or persons in whose presence they desire to appear; in other words, persons must be mediumistic to produce such manifestations of form.]
"Another such hideous monster is the Basilisc, created by Sodomy, and also the Aspis and Leo. There are innumerable bastard forms, half man, half spiders or toads, &c., inhabiting the astral plane, belonging to the 'serpent which is to have his head crushed by the heel of Christ'."  (Fragm.)
[15. John Scheffler ** says: "If you could see the horrible monsters by which you are surrounded you would be sick from disgust."]
[** Pseud. Angelus Silesius, [Wikipedia] a.k.a. Johann Scheffler, a 17th century follower of Jacob Boehme. ]
"If such forms are sufficiently dense to become visible, they appear like a coloured shadow or mist, or black shadows. They have no life of their own, but they borrow it from the person who called them into existence, just as a shadow is cast by a body; and where there is no body, there can be no shadow. They are often generated by idiots, immoral, depraved, or diseased persons, who lead irregular and solitary lives, and who are addicted to bad habits."
"The coherence of the particles composing the bodies of such beings is not very strong, and they are afraid of draughts of air, light, fire, sticks, and weapons. They are a sort of airy appendix to the body of their creator, and there is sometimes such an intimate connection between them and the body of their progenitors, that if an injury is inflicted upon the former, it will be transmitted to the latter. They are parasites drawing vitality out of the persons to whom they are attracted, and they exhaust their vitality very soon, if such persons are not very strong." 
[16. Paracelsus gives here a very good description of some of the modern spirit-materialisation. The "airy appendix" (astral form) usually comes out of the left side of the medium, in the region of the spleen. Mediums need not necessarily be depraved persons, but there must be some fault in their organisation, else the combination of their principles would be too strong to part with some of their astral substance. Materialising mediums may be very good people, but solitary lives and vicious habits lead to the development of such mediumship, which proves to be very injurious in the end.]
"Some such beings influence men according to their qualities; they watch them, increase and deepen their faults, find excuses for their mistakes, cause them to wish for the success of evil actions, and gradually absorb their vitality. They fortify and support the imagination in the operations of sorcery; they sometimes utter false prophecies and give out misleading oracles."
"If a man has a strong and evil imagination, and wishes to injure another, such beings are always ready to lend a helping hand for the accomplishment of his purpose." Such beings render their victims insane, if the latter are too weak to resist their influence.
"A healthy and pure person cannot become obsessed by them, because such Larvae can only act upon men if they make room for them in their minds. A healthy mind is a castle that cannot be invaded without the will of its master; but if lusts are allowed to enter, they excite the passions of men and women, they create cravings in them, they produce bad thoughts which act injuriously upon the brain; they sharpen the animal intellect and suffocate the moral sense."
"Evil spirits obsess only those human beings in whom the animal nature is preponderating. Minds that are illumined by the spirit of truth cannot be possessed; only those who are habitually guided by their own lower impulses will become subjected to their influence. Exorcisms and ceremonies are useless in such cases. Praying  and abstinence from all thoughts that stimulate the imagination or excite the brain are the only true remedies." (De Ente Spirituali)
[17. By "praying" is meant the exercise of the spiritual will. "Oh, you stupid and foolish priest, who know absolutely nothing; because you imagine to be able to drive away evil spirits with sweet-smelling incense, such as is enjoyed by good and evil spirits alike. If instead of your incense you were to take asafoetida, then might you succeed in driving away the evil spirits and the good ones besides." (Philos. Occulta)]
"The cure of obsession is a purely psychical and moral act. The obsessed person should use true prayer and abstinence, and after that a strong-willed person should will such spirits to depart." (Philosophia, Occulta) 
[18. It often happens that bodily diseases are the cause of morbid desires. A disease of the skin (pruritus vaginae or scroti) causes erotic desires; a displacement of the womb, an erosion, ulcer, or inflammation of the os uteri, cause mental depression and hysteria; piles cause melancholy, &c., &c.; but all such causes are, in their turn, the effects of previous causes having a psychical origin, and they establish the conditions by which elementary influences act.]
The reason why we cannot see such astral entities is because they are transparent as air. We cannot see the air unless we produce a smoke in it, and even in that case we do not see the air itself, but the smoke that is carried by the air. But we can feel the air when it moves, and we may also occasionally feel the presence of such entities, if they are dense enough to be felt.
Moreover, the purpose of our senses is to perceive the objects that exist on the plane for which those senses are adapted, and therefore the physical senses exist for the purpose of seeing physical things, and the senses of the inner man are made to see the things of the soul. When the outer senses are inactive, the inner senses awaken to life, and we may see the objects on the astral plane as we see things in a dream.
There are also some poisons by which the organic activity of the body can be suppressed for a time, and the consciousness of the inner man be rendered more active, and which will therefore enable us to see the things on the astral plane. But such poisons are destructive of reason and very injurious to the health. In fevers, deliriums, &c., such things may also be seen. Some of them are the creations of the mind of the patient; others may have been created by the morbid imagination of another person, as described above.
[19. Experiments that have been made in London, with the inhalation of various ethers, chloroform, nitrous oxide gas, and hydrocarbonates, have had the effect of producing such "hallucinations." Before these gases were known, fumigations of poisonous substances were used for such purposes. The receipts for the materials used for such fumigations were kept very secret, on account of the abuse that might have been made of such a knowledge, and in consequence of which a person may be even made insane. One of the most effective fumigations for the purpose of causing apparitions were, according to Eckartshausen, made of the following substances: Hemlock, Henbane, Saffron, Aloe, Opium, Mandrake, Solanum, Poppy-seed, Asafoetida, and Parsley. The fumigations to drive away evil spirits were made of Sulphur, Asafoetida, Castoreum, and more especially of Hypericum and Vinegar. Carbolic Acid was not known at that time.]
But if such entities are invisible under normal conditions to a human being, they will be well enough perceived by a human Elementary consciously existing on their plane, and, what is still more, depraved human characters after death take themselves the forms of animals and monsters, whom they were brought to resemble by their own evil thoughts. Form is nothing but an appearance representing a character, and the character shapes the form. If the character of a person is thoroughly evil, it will cause the astral form to assume a hideous form. Therefore the souls of the depraved appear in animal shapes.
[20. This is confirmed by Swedenborg [Wikipedia] in his description of "Hell," and also by Jacob Boehme. The animal soul of the departed takes the form and shape of that animal whose character predominated in his constitution.]
Pure spirit has no form: it is formless, like the sunshine. But as the sunshine causes the elements of matter to grow into plants, soul-substances are formed into beings having shapes, through the action of the spiritual rays. There are good spirits and spirits of evil; planetary spirits and angels. There are the spirits of the four elements, and there are many thousand different kinds.
[21. There is a never-ending chain of births and transformations taking place in the world of causes (spirits), as in the world of effects (forms). The lives of some such entities extend over enormous periods of time; others have only a short individual existence. According to the Brahminical teachings there are seven main classes of spirits, some of them having innumerable subdivisions:
- Arupa Devas (formless spirits), planetary spirits -- the intelligent sixth principle of the planet whose product they are.
- Rupa Devas (having forms). High planetary spirits. Dhyan-Chohans.
- Pisachas and Mohinis -- male and female Elementaries consisting of the astral forms of the dead, that may be obsessed by Elementals, and cause Incubi and Succubi.
- Mara rupas: forms of desire or passion. Souls doomed to destruction.
- Asuras: Elementals (Gnomes, Sylphs, Undines, Salamanders, &c.). They will develop into human beings in the next Manvantara (cycle of evolution).
- Beasts. Elementals having animal forms, monstrosities.
- Rakshasas or demons. Souls of sorcerers and of men with great intelligence, but with evil tendencies. Criminals for the advancement of science, dogmatists, sophists, vivisectionists, &c., furnish material for the development of such "devils."
The Asuras are often called Devas, and are worshipped in many places of India. They are the guardian spirits of certain places, gardens, houses, &c., and have temples of their own. There are many thousand varieties. (See Isis Unveiled in /blavatsky/ )]
"Each child receives at the time of its birth a familiar spirit or genius, and such spirits sometimes instruct their pupils even while the latter are in their earliest youth. They often teach them to do very extraordinary things. There is an incalculable number of such genii in the universe, and we may learn through them all the mysteries of the Chaos in consequence of their connection with the Mysterium magnum. Such familiar spirits are called Flagae." 
[22. They are evidently a different class of "familiar spirits" than the "invisible guides" mentioned above. The spirit which each child receives at its birth, and who attends to the person during his terrestrial life, is his own spiritual self, the "Karana sharira."]
"There are several kinds of Flagae, and there are two ways by which we may obtain knowledge through them. One way is by their becoming visible and able to talk with us; the other way is by their exercising an invisible influence upon our intuition. The art of Nectromancy  enables man to perceive interior things, and there is no mystery concerning any human being that may not be found out by that art, and the Flagae can be made to reveal it either by persuasion or by the strength of one's will, for the Flagae obey the will of man for the same reason that a soldier obeys the will of the commander, or an inferior obeys that of his superior, although the former may be physically stronger than the latter.
[23. Nectromancy is not to be confounded with Necromancy. See chapter 2.]
The Flagae can be made to appear visibly in a mirror of Beryl, in a piece of coal or a crystal, &c.; and not only the Flagae themselves, but the persons to whom they belong, may be seen, and all their secrets be known. And if it is not practicable to cause them to become visible, such secrets can be found out by a communication of thought, or by signs, allegorical visions, &c."
"By the assistance of these Flagae hidden treasures may be found and closed letters be read, and everything secret be seen, no matter how much it is hidden from outward sight, for the opening of the interior sight removes the veil of matter. Things that have been buried will thus be found, stolen goods recovered, &c." 
"The Flagae reveal their secrets to us in our dreams, the good as well as the evil. He who obtains knowledge from the spirit obtains it from his father; he who knows the Elementals knows himself; he who understands the nature of the elements understands how the Microcosm is constructed. The Flagae are the spirits that instructed mankind in arts and sciences in ancient times, and without them there would be no science or philosophy in the world." 
[25. The whole of the universe is an expression of consciousness, and there are, therefore, innumerable states of conscious and intelligent will in the world; some in visible and others in invisible form; some shapeless, like currents of air; others undefined, like mists or clouds; others solid, as rocks; some impermanent; others permanent, like the stars.]
"In the practice of divination by sortilegium [drawing lots], &c., the Flagae guide the hand. Such arts are neither from God nor from the devil, but they are from the Flagae. The ceremonies that are customarily used on such occasions are mere superstition, and have been invented to give to such occasions an air of solemnity. Those who do practise that art are often themselves ignorant of the laws that control it, and they perhaps attribute the results obtained to the ceremonies, and mistake tomfooleries for the essential thing." 
[26. The rationale on which divination, geomancy, the practice of the divining-rod, &c., is based, is that by means of such practices a knowledge in regard to certain things, such as already exists in the spirit of man, may come to the understanding of the intellect of his own personality. The inner man cannot, under all circumstances, communicate his knowledge to the external man, because the consciousness of the two is not identical; but the spirit may influence the nerve aura of the person and control the muscles of his body, and thus guide his hands.]
[Also see Roy Vincent's dowsing experiments in the Hearing Voices section of this site, chapter 6: ]
In regard to the reliance to be put on the revelations of invisible beings, Paracelsus says: "Evil spirits love to lead men into error, and therefore their prophecies are usually unreliable and their predictions based upon trickery. God made spirits mute, so that they may not tell everything so plainly to man that man does not need to use his reason to avoid making mistakes. The spirits should not instruct man; but they do not always obey that command. Therefore they are often silent when their speech is mostly needed, and they frequently speak false when it is of the utmost importance to know the truth. This is the cause that so many things that have been told by spirits have been proved lies and illusions, and some spirits lie a great deal more than others."
"But it may happen that perhaps out of a dozen predictions made by such spirits one accidentally comes out true, and ignorant people will in such cases pay no attention to the fact that the other eleven predictions were false, but they will be ready to believe everything that such spirits say. Such spirits often teach those persons who deal with them to perform certain ceremonies, to speak certain words and names in which there is no meaning, and they do all such things for their own amusement, and to have some sport at the expense of credulous persons."
"They are seldom what they pretend to be; they accept names, and one will use the name of another, or they will assume the mask and the ways of acting of another. If a person has such a spirit, belonging to a better class, he may make a good fortuneteller; but one who has a lying spirit will hear nothing but lies; and, on the whole, all these spirits surpass each other in deception and lies." (Philosophia Sagax) 
[27. Those who have some experience in modern spiritualism will recognize the truth of this description. Spiritualists should not act upon the advices of spirits, if such advices are against their own reason, and scientists should not rely on the opinions of others, if such opinions are against common sense.]
"Man is an instrument through which all the three worlds -- the spiritual, the astral, and the elementary world -- are acting. In him are beings from all these worlds, reasonable and unreasonable, intelligent and unintelligent creatures. A person without any self-knowledge and self-control is made to act according to the will of these creatures; but the true philosopher acts according to the will of the Supreme, the Creator, in him."
"If the masters whom man obeys are foolish, their servants will also act foolishly. It is true that every one thinks that he is the master, and that he does what he pleases; but he does not see the fool within him, who is his master, and by whom he becomes a fool himself." (De Meteoris)
There is another class of spirits, the Saganae or Elemental Spirits of Nature. Paracelsus says about their bodies: "There are two kinds of flesh -- one that comes from Adam and another that does not come from Adam. The former is gross material, visible and tangible for us; the other one is not tangible and not made from earth. If a man who is a descendant from Adam wants to pass through a wall, he will have first to make a hole through it; but a being who is not descended from Adam needs no hole or door, but may pass through matter that appears solid to us, without causing any damage to it."
"The beings not descended from Adam, as well as those descended from him, are organised and have substantial bodies; but there is as much difference between the substance composing their bodies as there is between Matter and Spirit. Yet the Elementals are not spirits, because they have flesh, blood, and bones; they live and propagate offspring; they eat and talk, act and sleep, &c., and consequently they cannot be properly called 'spirits.'"
"They are beings occupying a place between men and spirits, resembling men and women in their organisation and form, and resembling spirits in the rapidity of their locomotion. They are intermediary compound beings, formed out of two parts joined into one; just as two colours mixed together will appear as one colour, resembling neither one nor the other of the two original ones."
"The Elementals have no higher principles; they are therefore not immortal, and when they die they perish like animals. Neither water nor fire can injure them, and they cannot be locked up in our material prisons. They are, however, subject to diseases. Their costumes, actions, forms, ways of speaking, &c., are not very unlike those of human beings; but there are a great many varieties. They have only animal intellects, and are incapable of spiritual development." (Lib. Philos., ii.)
"These spirits of Nature are not animals; they have a reason and language like man; they have minds, but no spiritual soul. This may appear strange and incredible; but the possibilities of nature are not limited by man's knowledge of them, and the wisdom of God is unfathomable."
"They have children, and these children are like themselves. Man is made after the image of God, and they may be said to be made after the image of man; but man is not God, and the elemental spirits of Nature are not human beings, although they somewhat resemble man. They are liable to sickness, and they die like animals. Their habits resemble those of men; they work and sleep; they eat and drink and make their clothing; and as man is nearest to God, so are they nearest to man."  (Lib. Philos., i.)
[28. Man in his aspect as a terrestrial being, and if we leave the divine principle out of our consideration, is himself an elemental spirit of Nature, composed of all the four elements; but as he lives and breathes in the air, he may be called an elemental of the air walking upon the earth.]
"They live in the four elements: the Nymphae in the element of water, the Sylphs in that of the air, the Pigmies in the earth, and the Salamanders in the fire. They are also called Undinae, Sylvestres, Gnomi, Vulcani, &c. Each species moves only in the element to which it belongs, and neither of them can go out of its appropriate element, which is to them as the air is to us, or the water to fishes; and none of them can live in the element belonging to another class. To each elemental being the element in which it lives is transparent, invisible, and respirable, as the atmosphere is to ourselves."
"The four classes of Nature-spirits do not mix with each other; the Gnomes have no intercourse with the Undines or Salamanders, nor the Sylvestres with either of these. As a fish lives in the water, it being its element, so each being lives in its own element."
"For instance, the element wherein man breathes and lives is the air; but to the Undines the water is what the air is to us, and if we are surprised that they are in the water, they may also be surprised because we are in the air. Thus the element of the Gnomes is the earth, and they pass through rocks and walls and stones like a thought; for such things are to them no greater obstacles than the air is to us."
[As do radio waves. - editor]
"In the same sense the fire is the air wherein the Salamanders live; but the Sylvestres are the nearest related to us, for they live in the air like ourselves; they would be drowned if they were under water, and they would suffocate in the earth and be burned in the fire; for each being belongs to its own Chaos and dies if transported into another."
"If that Chaos is gross, the beings living in it are subtle; and if the Chaos is subtle, the beings are gross. Therefore we have gross bodies, so that we can pass through the air without being blown down, and the Gnomes have subtle forms, so as to be able to pass through the rocks. Men have their leaders and authorities; bees and ants their queens; geese and other animals have their leaders; and so also have the spirits of Nature their kings and queens. The animals receive their clothing from Nature; but the spirits of Nature prepare it themselves."
"The omnipotence of God is not limited to His taking care only of man, but is abundantly able to take care also of the spirits of Nature, and of many other things of which men know nothing. They see the sun and the sky the same as we, because each element is transparent to those who live therein. Thus the sun shines through the rocks for the Gnomes, and the water does not hinder the Undines to see the sun and the stars; they have their summers and winters, and their 'earth' bears them fruits; for each being lives on that element whereof it has grown." (Lib. Philos., ii.)
"As far as the personalities of the Elementals are concerned, it may be said that those belonging to the element of water resemble human beings of either sex; those of the air are greater and stronger; the Salamanders are long, lean, and dry; the Pigmies are of the length of about two spans, but they can extend or elongate their forms until they appear like giants."
"The Elementals of air and water, the Sylphs and Nymphs, are kindly disposed towards man; the Salamanders cannot associate with him on account of the fiery nature of the element wherein they live, and the Pigmies are usually of a malicious nature."
"The Pigmies are building houses, vaults, and strange-looking edifices of some certain semi-material substances unknown to us. They have some kind of alabaster, marble, cement, &c.; but these substances are as different from ours as the web of a spider is different from our linen. Nymphs have their residences and palaces in the element of water; Sylphs and Salamanders have no fixed dwellings."
"On the whole, the Elementals have an aversion against self-conceited and opinionated persons, such as dogmatists, inquisitive sceptics, drunkards, and gluttons, and against vulgar and quarrelsome people of all kinds; but they love natural men, who are simple-minded and child-like, innocent and sincere, and the less there is vanity and hypocrisy in a man, the easier will it be for him to approach them; but otherwise they are as shy as wild animals." 
[29. There is nothing very strange in the belief that such "spirits" exist, if we only keep in mind that the best part of ourselves is an invisible spirit of unknown dimensions, occupying and overshadowing a limited material form.]
"Man lives in the exterior elements, and the Elementals live in the interior elements. They have dwellings and clothing, manners and customs, languages and governments, of their own, in the same sense as the bees have their queens and herds of animals their leader. They are sometimes seen in various shapes. Salamanders have been seen in the shapes of fiery balls, or tongues of fire running over the fields or appearing in houses. Nymphs have been known to adopt the human shape, clothing, and manner, and to enter into a union with man."
[30. The "soul" of the elements; i.e., their ethereal aspects.]
"There are certain localities where large numbers of Elementals live together, and it has occurred that a man has been admitted into their communities and lived with them for a while, and that they have become visible and tangible to him." 
[31. It is not credible that a person has entered with his physical body into the Venus mountain or Untersberg, or any other such renowned places of which popular tradition speaks. Neither have the witches and sorcerers of the Middle Ages been at the witch-sabbath in their physical bodies, and it seems equally improbable that a person should ever have entered physically the abodes of disembodied adepts. But the physical body of a man is not the man; it is only his external shadow, and wherever man's consciousness is, there will he be present himself. But while he is there, he does not miss his exterior body, of which he has no more use than of a part of his clothing purposely laid away, and on reawakening to physical consciousness he may well believe that he had been to such a place in his physical form.]
"The angels are invisible to us; but nevertheless an angel may appear to our spiritual sight, and likewise man is invisible to the spirits of nature, and what the Undines know of us is to them merely what fairy tales are to us. The Undines appear to man, but not man to them. Man is gross in the body and subtle in the Chaos; therefore they may enter his Chaos (the physical plane), and appear to him and remain with him, marry and have children with him."
"Thus an Undine may marry a man and keep house with him, and her children will be human beings and not Undines, because they receive a human soul from the man; and, moreover, the Undine herself thereby receives the germ of immortality. Man is bound to God by means of his spiritual soul, and if an Undine becomes united to man, she will thereby become bound to God. As an Undine without her union with man dies like an animal, likewise man is like an animal if he severs his union with God."
"Therefore the Nymphs are anxious to become united with man; they seek to become immortal through him. They have a mind and intellect like man, but not the immortal soul, such as we have obtained through the death of Christ. But the spirits of the earth, the air, and fire seldom marry a human being. They may, however, become attached to him and enter his service. It must not be supposed that they are airy nothings or merely ghosts or appearances; they are of flesh and blood, only subtler than man." (i.e., of the substance of mind)
"The Nymphs sometimes come out of the water and may be seen sitting on the shore near their dwelling, and they as well as the Gnomes have a language like man; but the spirits of the woods are more rough and speak nothing, although they are able to speak and are clever. The Nymphs appear in human form and clothing; but the spirits of fire are of a fiery shape. They are usually not to be found in the company of men; but they come to cohabit with old women, such as are witches, and they are sometimes obsessed by the devil."
"If any man has a Nymph for a wife, let him take care not to offend her while she is near the water, as in such a case she might return to her own element;  and if any one has a Gnome for a servant, let him be faithful to him, for each has to be dutiful to the other; if you do your duty to him, he will do his duty to you. All this is in the divine order of things and will become manifest in due time; so that we will then be able to see that which seems now almost incredible." (Lib. Philos., ii.)
[32. "If anyone marries a water-nymph, and she deserts him, he ought not to take another wife, for the marriage has not been dissolved. If he marries another woman he will shortly die." (De Nymph.)]
In the legends of the saints the Elemental spirits of Nature are often alluded to as "devils," a name which they do not deserve, because there are good as well as bad Elementals; but, although some may be very selfish, they have not developed any love for absolute evil, because they have only mortal souls, but no spiritual essence to make them immortal.
Besides the astral spirits in man and the Elemental spirits of Nature, there are many other spirits born within the soul (the will and imagination of Nature); and as the mind of man may create monsters, and man paint their images on canvas, or sculpture them in stone or wood, so the universal power of Nature's mind creates monsters in the astral light, and they will throw their shadows forth in the physical world of appearances, by becoming objective in corporeal bodies upon the earth. Some of them are short-lived, and others will live unto the day of the dissolution of all things.
"We all know that a man may change his character in the course of his life, so that he ultimately becomes a very different person from what he was before; and thus every creature having a will can change and become supernatural or unnatural; i.e., different from that which normally belongs to its nature. Many of the head-lights of the Church, who now strut about with jewels and diamonds, will be dragons and worms when the human body in which they are now masquerading will have disappeared at the time of their death." (Lib. Philos., iv.)
"There are the Sirens, but they are merely a kind of monstrous fishes; but there are also two more kinds of spirits, related to the Nymphs and Pigmies, namely, the Gigantes (giants) and the Dwarfs. This may not be believed, but it ought to be remembered that the beginning of true knowledge is that the light of Nature illumines man, and that in this light he knows all things in Nature by means of the light of the inner man."
[33. Italicore Catacca (Mermaid).]
"The Giants and Dwarfs are monsters, being related to the Sylvestres and Gnomes in the same sense as the Sirens are related to the Undines. They have no (spiritual) souls, and are rather to be compared to monkeys than to human beings. Such spirits are often the guardians of hidden treasures."
"Such things will be denied and ridiculed by the worldly wise; but at the end of the world, when all things will be revealed, then will also come forward the so-called 'doctors' and 'professors,' who were great in their ignorance; then will it be seen who were those that were learned in the foundation of Nature, and the others learned in empty talk."
"Then we will know those who have written according to truth and those who taught according to their own fancy; and each one will receive what he deserves. There will then be no doctors and no magisters, and those who are now making a great deal of parade and noise will then be very silent; but those who have received the true understanding will be happy. Therefore I recommend my writings to be judged at that time when all things will become manifest, and when each one will see the light as it was revealed to him."
"The evil spirits are, so to say, the bailiffs and executioners of God (Karma). They have been called into existence by the influences of evil, and they work out their destiny. But the vulgar have a too high estimate of their powers, especially of the power of the devil. The devil has not enough power to mend a broken pot, much less to enrich a man. He -- or it -- is the poorest thing that can be thought of, and poorer than any being that can be found in the four elements." 
[34. The "devil" is evil spiritual will. The devil has no power over man; but if man allows a devil within himself to grow, then will the great Devil aid the little devil to grow and nourish him with his own substance. (See "The Doctrines of Jacob Boehme.") [Scan of pdf is in the Christian section of this site: /christian/ ]]
"There are a great many inventions, sciences, and arts that are ascribed to the agency of the (personal) devil; but before the world grows much older it will be found that the devil has nothing to do with such things, that the devil is nothing and knows nothing, and that such things are the results of natural causes. True science can accomplish a great deal; the Eternal Wisdom of the existence of all things is without a time, without a beginning, and without an end. Things that are considered now to be impossible will be accomplished; that which is unexpected will in future prove to be true, and that which is looked upon as superstition in one century will be the basis for the approved science of the next." (Philosophia Occulta)