Because of irregularities in the orbital motions of Mercury, scientists once thought there had to be a planet orbiting the Sun closer than Mercury orbits it. The gravity of this extra planet, tugging on Mercury, might explain Mercury's strange motions. They gave the hypothetical innermost planet the name "Vulcan." They couldn’t see Vulcan, but they assumed this was because the glare of the Sun hid the planet from view. Later, they realized that Vulcan does not exist. Einstein's theory of relativity explains the oddities of Mercury's motions.

Like several real planets (Saturn, Mars, Venus...), the unreal planet Vulcan takes its name from an ancient god. The Roman god of fire was called "Vulcan." 

Steiner used the name "Vulcan" in at least two distinct ways. Sometimes, when speaking of Vulcan, he meant the planet. On other occasions, he meant a distant stage of evolution: Future Vulcan. Steiner taught that the entire solar system evolves, and as it does so it takes different forms. The first form of the solar system was "Old Sun." The seventh form — far in our future — will be "Future Vulcan."

Here is a collection of statements Steiner made about Vulcan — the god, the planet, and the evolutionary stage.

We’ll start with what is perhaps Steiner’s most important statement about Vulcan, since it appears in his most important book. It clearly refers to Vulcan as a stage of evolution. Unfortunately, in all other ways, its is singularly uninformative:

“During [the Venus] state [i.e., stage of evolution] a special cosmic body splits off that contains all the beings who have resisted evolution, a so to speak ‘irredeemable moon,’ which now moves toward an evolution, for the character of which no expression can be found because it is too dissimilar to anything that man can experience on earth. The evolved mankind, however, advances in a completely spiritualized existence to the Vulcan evolution  [i.e., stage of evolution], the description of which does not lie within the scope of this book.” — Rudolf Steiner, OUTLINE OF OCCULT SCIENCE (Anthroposophic Press, 1972), chapter 6, GA 13.

The following quotation is tantalizing. “Oracles” are places where occult wisdom, such as knowledge of the future, can be found. The presiding savants in such places are also sometimes called oracles. Steiner said there were seven oracles on the continent of Atlantis, and he said the seven oracles were associated with “the seven planets.”*

“Of the seven oracles, which were named after the seven planets in ancient Atlantis, the Sun Oracle stood out from all the others, but next to it the Vulcan Oracle prepared itself in secrecy for its future task.” — Rudolf Steiner, THE PRINCIPLE OF SPIRITUAL ECONOMY (Anthroposophic Press, 1978), lecture 9, GA 109.

This next quotation is long, but stay with it. Steiner seems to say that Vulcan exists in the solar system today, perhaps not as a planet but as a “sphere” (a term he used to denote the area of the solar system bounded by the orbit of a planet). This gets a bit confusing, since the “sphere” of Vulcan would have to be the area bounded by the orbit of the planet Vulcan — but does Vulcan exist as a planet? And, come to that, do the planets orbit the Sun? Steiner sometimes said that they do, but he also sometimes said that they don’t. [See “Deception”.]

Be all that as it may, here’s what Steiner said about "Vulcan men" and "Vulcan beings." Background: At an early stage of life on Earth, human souls fled to the other planets. (Weren't you taught this in school?) Then, during the age of Atlantis, these souls returned to Earth — they came from planets such as Saturn, Mars, and Vulcan (see the references, below, to “Vulcan men”). Moreover, Steiner says that “Vulcan Beings” or “’Supermen’ of Vulcan” are coming to Earth today. Where are they coming from? Vulcan.

“Whereas in ancient Atlantean times these human beings descended to earth from Saturn, Jupiter, Mars, and the other planets — and it was therefore a matter of human soul beings entering the earth existence then — now a time is beginning when beings who are not human are coming down to earth from cosmic regions beyond. These beings are not human but depend for the further development of their existence on coming to earth and on entering here into relationships with men.

“Thus, since the eighties of the nineteenth century, heavenly beings are seeking to enter this earth existence. Just as the Vulcan men were the last to come down to earth,  so Vulcan beings are now actually entering this earth existence. Heavenly beings are already here in our earth existence. And it is thanks to the fact that beings from beyond the earth are bringing messages down into this earthly existence that it is possible at all to have a comprehensive spiritual science today.

“Taken as a whole, however, how does the human race behave? If I may say so, the human race behaves in a cosmically rude way toward the beings who are appearing from the cosmos on earth, albeit, to begin with, only slowly. Humanity takes no notice of them, ignores them. It is this that will lead the earth into increasingly tragic conditions. For in the course of the next few centuries, more and more spirit beings will move among us whose language we ought to understand. We shall understand it only if we seek to comprehend what comes from them, namely, the contents of spiritual science. This is what they wish to bestow on us. They want us to act according to spiritual science; they want this spiritual science to be translated into social action and the conduct of earthly life.

“Since the last third of the nineteenth century, we are actually dealing with the influx of spirit beings from the universe. Initially, these were beings dwelling in the sphere between moon and Mercury, but they are closing in upon earth, so to say, seeking to gain a foothold in earthly life through human beings imbuing themselves with thoughts of spiritual beings in the cosmos. This is another way of describing what I outlined earlier when I said that we must call our shadowy intellect to life with the pictures of spiritual science. That is the abstract way of describing it. The description is concrete when we say: Spirit beings are seeking to come down into earth existence and must be received. Upheaval upon upheaval will ensue, and earth existence will at length arrive at social chaos if these beings descended and human existence were to consist only of opposition against them. For these beings wish to be nothing less than the advance guard of what will happen to earth existence when the moon reunites once again with earth.

“Nowadays it may appear comparatively harmless to people when they think only those automatic, lifeless thoughts that arise through comprehension of the mineral world itself and the mineral element's effects in plant, animal, and man. Yes, indeed, people revel in these thoughts; as materialists, they feel good about them, for only such thoughts are conceived today. But imagine that people were to continue thinking in this way, unfolding nothing but such thoughts until the eighth millennium when moon existence will once more unite with the life of the earth. What would come about then? The beings I have spoken about will descend gradually to the earth. Vulcan beings, Vulcan supermen, Venus supermen, Mercury supermen, sun supermen, and so on will unite themselves with earth existence. Yet, if human beings persist in their opposition to them, this earth existence will pass over into chaos in the course of the next few thousand years.” — Rudolf Steiner, MATERIALISM AND THE TASK OF ANTHROPOSOPHY (Rudolf Steiner Press, 1987), lecture 14, GA 204.

So, as you can see, we must accept Steiner's teachings or face an inconceivably horrid future. Notice, too, that we can have "a connected body of Spiritual Science" — that is, Anthroposophy — because beings such as "Vulcan beings, Vulcan supermen" bring us their wisdom.

[R.R., 21st Century.]

 .

The next quotation essentially repeats what we have already seen, but I offer it to stress the point that Steiner treats Vulcan as a real planet, a physical location in the solar system comparable to the other planets.

“You will remember the passage in the book OCCULT SCIENCE dealing with the time when the human souls ascended to the planets and afterwards descended once more to earth-existence. I spoke of how the Mars-men, the Jupiter-men and the others descended again to earth. Now an event of great significance came to pass at the end of the seventies of last century [i.e., the 1870’s]. It is an event that can be described only in the light of facts which are revealed to us in the spiritual world. Whereas in the days of old Atlantis human beings came down to the earth from Saturn, Jupiter, Mars, and so on — that is to say, beings of soul were drawn into the realm of earth-existence — since the end of the seventies of last century, other Beings — not of the human order — have been descending to the earth for the purposes of their further development. From cosmic realms beyond the earth they come down to the earth and enter into a definite relationship with human beings. Since the eighties of the nineteenth century, super-earthly Beings have been seeking to enter the sphere of earth-existence. Just as the Vulcan-men were the last to come down to the earth so now Vulcan Beings are actually coming into the realm of earthly existence. Super-earthly Beings are already here, and the fact that we are able to have a connected body of Spiritual Science [i.e., Anthroposophy] at all today is due to the circumstance that Beings from beyond the earth are bringing the messages from the spiritual world down into earth-existence.” — Rudolf Steiner, “A Picture of Earth-Evolution in the Future” (THE GOLDEN BLADE, 1960), a lecture, GA 204.

Here’s an interesting passage. In it, Steiner speaks of “recapitulation” — the notion that at each stage of evolution, prior stages are repeated in an altered form. Note that during a repetition of the Saturn stage, Vulcan broke away from the Earth to become a separate planet. The "retarded beings" Steiner refers to are evil souls who fall behind — or out of — the proper course of evolution. Essentially, these are souls who do not embrace Steiner's teachings.

“During the recapitulation of the Saturn embodiment, Uranus, Vulcan and Saturn separated from the earth. During the recapitulation of the Sun embodiment, Jupiter and Mars separated. After the sun has left the earth, Mercury and Venus separate from it. After the separation of the sun, the earth cast out the moon. The dispersal of Old Moon was brought about by the forces of the progressed beings who drew out the solar body, while the normal and retarded beings produced the moon circling around it. In all the Mysteries these happenings were called the strife in heaven. The detached planetoids are the ruins of that battlefield. It is here that the primal secret of the origin of evil must be sought.” — Rudolf Steiner, ROSICRUCIAN ESOTERICISM  (Anthroposophic Press, 1978), lecture 7, GA 109.

We should remember that Steiner wrote and spoke in German, and English translations of his remarks are not necessarily reliable. Still, it is interesting to note statements in which Steiner refers to life “on” various planets, including Vulcan. (To unscramble statements like the following, it may help to remember that according to Steiner planets exist, in varying forms, during periods that bear their names, even if a clear distinction can be made between a planet and its namesake period. Thus, for instance, today we live on the planet Earth in the form this planet has assumed during the evolutionary stage called Present Earth. Likewise, the planet Vulcan might possibly still exist as a planet, in some form, during the future evolutionary period called Future Vulcan. Then, too — and this more accurately reflects Steiner's teachings — we may say that during Future Vulcan the entire solar system will exist in a highly spiritualized form which may be called Vulcan. In that case, saying that we will live "on" Vulcan or "in" Vulcan or "during" Vulcan may all boil down to the same thing. The solar system, or as it were the "world," will be Vulcan.) 

“On the future Venus a complete consciousness in the etheric body will develop. Then, while man sleeps, he will gain a consciousness concerning the other side of the world. On Vulcan the spirit is completely detached; he has then taken the etheric body also with him. This condition endows man with an exact knowledge of the entire world.” — Rudolf Steiner, FOUNDATIONS OF ESOTERICISM (Rudolf Steiner Press, 1982), lecture 25, GA 93a.

Like other occultists, Steiner read great meaning into numbers. [See "Magic Numbers".] Hence, he found a wonderful correspondence between the seven planets and the seven forms of human consciousness. Steiner's followers are impressed by such correspondences, finding them as "proof" of Steiner's teachings.

There are a few problems with this approach. 1) The Sun and Moon, which Steiner included in the roll of planets, are not planets. 2) Vulcan, which Steiner included in at least one form of the roll, is not a planet — it does not exist. 3) There are eight planets, not seven. The real planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. (There are nine planets if we could Pluto. Or ten if we count...) 4) The number of types of human consciousness may be seven — but it may also be any other number you care to specify. Try it. Can you think of an eighth form or consciousness? A thirteenth? A thirty-seventh? Sure you can. Give it a try. (The seven Steiner listed, beginning during Old Saturn and culminating during Future Vulcan, are in essence coma, deep sleep, dreaming, waking, imagination, inspiration, and intuition.)

"That the human being can pass through seven such planetary conditions is the meaning of evolution. Each planetary stage is bound up with the development of one of the seven states of human consciousness, and through what takes place on each planet the physical organs for such a state of consciousness are perfected. You will have a more highly developed organ, a psychic organ, on Jupiter; on Venus there will be an organ through which man will be able to develop physically the consciousness possessed by the initiate today on the Devachanic plane. And on Vulcan the Spiritual consciousness will prevail, which the initiate possesses today when he is in Higher Devachan, the World of Reason." — Rudolf Steiner, THEOSOPHY OF THE ROSICRUCIAN (Rudolf Steiner Press, 1966), lecture 8, GA 99.

I'll shut up now. Here are some more examples of Steiner's wisdom regarding Vulcan. (I'll hold my peace.)

"So much, so inconceivably much, has gone into our becoming what we are. And there is so inconceivably much contained in the Earth evolution that is still to come, and in our passage through the spheres of Jupiter, Venus and Vulcan! Only little by little does one disentangle oneself from the implications of current thought and approach that which, because it is more spiritual, is more difficult to conceive and is rarely touched on by the habitual thinking of people of today. Observing man as he presently is on Earth, we see that the seeds, so to speak, of what will develop during Jupiter, Venus and Vulcan already are hidden within him. But the human being is also the result of the Saturn, Sun and Moon spheres. Yesterday I said that wisdom and everything concerned with truth was established on Old Sun and will be completed on Jupiter....

"The seed that was planted on Old Sun will more or less complete its development on Jupiter. Thus we can say: The period within which truth develops stretches from Sun to Jupiter. On Jupiter truth will have become thoroughly inward, and so will have become wisdom: Truth becomes wisdom!

"Everything that belongs to the aesthetic sphere began on Old Moon. It will be completed on Venus. We could draw it in like this: From here, Moon, to completion here, Venus. This is where beauty develops. You see how it overlaps.

"Everything contained within these two streams — and the third stream, also — is actually resting unconsciously in the depths of our being. And now, on Earth, the sphere we can call the sphere of morality is beginning. It will be completed on Vulcan." — Rudolf Steiner, THE RIDDLE OF HUMANITY (Rudolf Steiner Press, 1990), lecture 5, GA 170.

"And now when the pupil felt everything flowing together into his heart which he had experienced earlier, just as I described it to you yesterday, all that he had experienced in his soul, manifested itself at the same time as the experience of the planet. Man has a thought. The thought does not remain within the skin of the man. The thought begins to resound. The thought becomes Word. That which the man lives forms itself into Word. In the Vulcan-planet the Word spreads itself out. Everything in the Vulcan-planet is speaking living Being. Word sounds to Word. Word explains itself by Word. Word speaks to Word. Word learns to understand Word. Man feels himself as the World-understanding Word, as the Word-world understanding Word.

"While this was present before the candidate for Initiation in Hibernia, he knew himself to be in the Vulcan existence, in the last metamorphosed condition of the earth-planet." — Rudolf Steiner, MYSTERY CENTRES (Garber Communications, 1985), lecture 9, GA 232.

"The course of evolution is this: a Sun, which from the beginning is included in such a system, has at first to throw off its planets, being too weak to develop further without excluding them. It grows strong, absorbs its planets again, and grows into a Vulcan. Then the whole is dissolved, and from the Vulcan globe is formed a hollow globe which is something like the circles of Thrones, Cherubim, Seraphim, etc. The Sun will thus dissolve in space, sacrifice itself, send forth its Being into the Universe, and through this will itself become a circle of Beings like the Thrones, Cherubim, Seraphim, which will then advance towards new creation." — Rudolf Steiner, SPIRITUAL HIERARCHIES (Anthroposophical Publishing Company, 1928), lecture 5, GA 110.

"The third aspect of the Logos is the creative power of the word (as expressed at the beginning of the Gospel of St. John), of which the words of human speech are the reflection. In the old myths and legends this truth was represented in the figure of Vulcan, the cripple. His mission was to guard the sacred fire. He is crippled because, in initiation, man must lose something of his lower, physical forces; the lower part of the body is a product of the past. Raised to the heights of initiation, the lower nature must fall away, to rise thereafter to a yet higher stage. Thus in the course of his evolution man has divided into a lower and higher nature." — Rudolf Steiner, AN ESOTERIC COSMOLOGY (Rudolf Steiner Press, 1978), lecture 10, GA 94.

"[T]he Vulcan human being limps. His legs are in retrogression; they cease to have significance. At the end of evolution, in the Vulcan metamorphosis of the Earth, man will be the three-membered being that the saga indicates as the ideal.” — Rudolf Steiner, FOUNDATIONS OF ESOTERICISM (Rudolf Steiner Press, 1982), lecture 3, GA 93a.

"Life proceeds with the greatest speed on Saturn, the rapidity then decreases on the Sun, becomes still less on the Moon and reaches its slowest phase on the earth. On the latter it becomes slower and slower, to the point at which self-consciousness develops. Then the speed increases again. Therefore, today man has already passed the time of the greatest slowness of his development. Life has begun to accelerate again. On Jupiter the speed of the Moon, on Venus that of the Sun will again be attained. The last planet which can still be counted among the series of earthly transformations, and hence follows Venus, is called 'Vulcan' by mystery science. On this planet the provisional goal of the development of mankind is attained. The condition of consciousness into which man enters there is called 'piety' or spiritual consciousness. Man will attain it in the seventh cycle of Vulcan after a repetition of the six preceding stages. Not much can be publicly communicated about the life on this planet. In mystery science one speaks of it in such a way that it is said, 'No soul which, with its thinking is still tied to a physical body, should reflect about Vulcan and its life.' That is, only the mystery students of the higher order, who may leave their physical body and can acquire supersensible knowledge outside of it, can learn something about Vulcan." — Rudolf Steiner, COSMIC MEMORY (Rudolf Steiner Publications, 1959), chapter 13, “The Earth and Its Future”, GA 11.

"After the Vulcan stage, man will develop yet further, and will ascend to still higher levels of consciousness. As the external eye looks into misty gray distances, so the inner eye of the seer looks upon five more forms of consciousness, as far off as distant spirits, of which a description, however, is quite impossible. In all, one can speak of twelve stages of consciousness.

"The Saturn man was surrounded by eleven other kinds of beings. The four highest had had their tasks on levels of development which preceded the life of Saturn. When this life began they had already arrived at such a high stage of development that their further existence took place in worlds which lie beyond the realms of man. Therefore, we cannot and need not speak of them here.

"The other kinds of beings, however — seven of them in addition to the Saturn man — are all concerned in the human development. In this they act as creative powers, performing their services in a way which will be described in the following pages.

"When the Saturn development began, the most sublime of these beings already had attained a level of consciousness which man will reach only after his Vulcan life, that is, a high creative (supra-spiritual) consciousness. These 'creators,' too, once had to pass through the stages of man. This took place on heavenly bodies which preceded Saturn. However, the connection of these beings with the development of mankind lasted until the middle of the life of Saturn. Because of their sublime, delicate body of rays, in mystery science they are called 'Radiating Lives' or 'Radiating Flames.' Because the substance of which this body consisted had a remote resemblance to the will of man, they are also called 'Spirits of Will.'

"These spirits are the creators of the man of Saturn. From their bodies they pour the substance which becomes the carrier of the human Saturn consciousness. The period of development during which this takes place is called the first small Saturn cycle. (In the language of theosophy, this is the 'first round.') The material body which man receives in this way is the first rudiment of his later physical body. One can say that the germ of the physical human body is planted during the first Saturn cycle by the Spirits of Will, and that at that time this germ has the dull Saturn consciousness.

"This first smaller Saturn cycle is followed by six others. In the course of these cycles man does not attain a higher degree of consciousness. But the material body which he has received is further elaborated. The other kinds of beings indicated above participate in this elaboration in the most diverse ways.

"After the 'Spirits of Will' there follow beings with a creative (spiritual) consciousness, similar to that which man will attain on Vulcan. They are called 'Spirits of Wisdom.'” — Rudolf Steiner, COSMIC MEMORY (Rudolf Steiner Publications, 1959), chapter 15, “The Life of Saturn”, GA 11.

"To unite Divinity with what is external, to make inward what is external — these are the two directions in which man makes progress in evolution. He will resemble Divinity more and more and will at last become more and more inwardly enriched. In the Vulcan stage of evolution everything will have been fructified. Everything external will have become internal. To become inwardly enriched — is to become Divine. That is the aim and the meaning of life." — Rudolf Steiner, ON THE MEANING OF LIFE (Rudolf Steiner Publishing Company, 1946, lecture 2, GA 155.

"Blood is the I's instrument. Saturn spirits work in the warmth of our blood, as Christ worked in Jesus' blood from age 30 on. Before that Jesus had worked on his physical, etheric and astral bodies. Then Christ took hold of the blood and purified it during the three years. That's why blood had to flow. When we've purified our four bodies in the same way we'll then have the four-fold philosophical fire that belongs to the Vulcan period." — Rudolf Steiner, FROM THE CONTENTS OF ESOTERIC CLASSES (transcript, Rudolf Steiner Archive), GA 266.

* In classical tradition, there are seven “sacred planets”: Saturn, Jupiter, Mars, Venus, Mercury, the Sun, and the Moon. Theosophists generally accept this concept, associating it with seven “planes of being.” [http://www.theosociety.org/pasadena/etgloss/pl-pral.htm] Vulcan is present but hidden and thus usually not listed. 

"Theosophy teaches that there is a planet, at present generally invisible to human scrutiny, closer to the sun than Mercury, and that it became generally invisible to human sight during the third root-race, after the fall of mankind into physical generation. The ancients spoke of seven sacred planets, and the sun was often enumerated as a substitute or blind for this planet." — ENCYCLOPEDIC THEOSOPHICAL GLOSSARY (Theosophical University Press, 1999).

Steiner used this classical/Theosophical roll when speaking of the physical solar system — he excluded Uranus and Neptune, saying they are not really members of the solar system, and he only rarely mentioned Vulcan (as a planet). There were times, however, when Steiner seemed to say that Vulcan is  one of the planets of our solar system.

When describing evolutionary history, Steiner again generally followed the Theosophical lead, teaching that there are seven planetary stages or conditions of consciousness: Saturn, Sun, Moon, Earth, Jupiter, Venus, and Vulcan — in that order.

Below is a rough sketch of a rough sketch Steiner tossed off. (I’ve made my own choice of colors.) Ranged along the top are the "planets": Saturn, Sun, Moon, Mars, Earth (green, vague), Mercury, Jupiter, Venus, and Vulcan. (Yes, Vulcan). At the bottom is the human being: physical body (blue) around the etheric body (orange) around the astral body (red) around a stack: reading, top to bottom, sentient soul, intellectual soul, consciousness soul, and "upper trinity" (i.e., manas, budhi, and atma). Each human part is connected to its equivalent planet. For example, 

“The human being was never on Mars, but his intellectual soul is connected esoterically with this planet in such a way that its forces have been taken from there.” — Rudolf Steiner, CORRESPONDENCE AND DOCUMENTS (Rudolf Steiner Press, 1988), p. 71. 

[My sketch, 2009, based on the one in the book.]

Here are the associations Steiner depicted: 

physical body: Saturn

etheric body: Sun

astral body: Moon 

sentient soul: Moon 

intellectual soul: Mars 

consciousness soul: Mercury

manas (spirit self): Jupiter

budhi (life spirit): Venus

atma (spirit man): Vulcan

Consistency was never Steiner's strong suit. Note that in this case, he names nine "planets."

— Compilation and commentary by Roger Rawlings

[R.R.]