Skyscript Astrology Forum

I have a theory about what the zodiac wheel symbolizes, it's not 100% polished yet but it's mostly coherent at this point. Feedback and criticism are always welcome. Forgive me for the overly technical presentation, hopefully you'll find the theory interesting enough to slog through the details.

The "Taijitu" (AKA the yinyang symbol) is a representation of the relationship between the opposing forces of yin and yang. The zodiac wheel has a similar meaning and the concepts of yin/yang seem identical to the Platonic spirit/matter schema:

The zodiac wheel represents the cyclical process of spirit turning into matter and matter turning back into spirit. This can be described in four phases:

1.The process begins with Aries, in which the Sun is exalted. The Sun symbolizes the quality of nous, spirit, form etc. At this point, Aries/the Sun represents 100% spirit and 0% matter.

2.In Cancer the process of emanation from Aries/the Sun results in an intermediate mixture of 50% spirit and 50% matter. The spirit proportion is decreasing while the matter proportion is increasing.
-Jupiter is exalted in Cancer which is appropriate since this point of the emanation process represents growth and expansion.

3.In Libra the process of emanation from Aries/the Sun reaches its maximum point. This represents a state of 0% spirit and 100% matter.
-Saturn is exalted in Libra which is appropriate since Saturn represents matter and is the antithesis of the Sun which represents spirit. BTW the demarcation of true manifestation into matter begins with Cancer and ends with Capricorn but Libra inbetween is representing something more abstract and less concrete, maybe like the perfect archetypal concept of matter.

4.In Capricorn the process of emanation from Aries/the Sun is nearly complete and results in an identical composition as the second phase with Cancer except this time the spirit proportion is increasing while the matter proportion is decreasing.
-Mars is exalted in Capricorn and symbolizes the idea of reduction or decrease, likewise at this phase the matter proportion is decreasing. After this phase you eventually end up back at Aries/the Sun which is once again 100% spirit.

The matching equal ascension sign for each cardinal sign helps fill out more of the schema. Keep in mind that the equal ascension sign helps out the sign that comes after it in zodiacal order, which is why I've placed the helping sign first and the helpee sign second:

Pisces/Venus => Aries/the Sun
-Venus is exalted in Pisces and represents the idea of unifying and bringing back together. Thus Pisces/Venus helps restore the oneness/completeness of Aries/the Sun.

Cancer/Jupiter => Sagittarius/South Node
-The ascendant Cancer (representing life) is handing over to the 6th house which represents illness ("pre-death"). I didn't fully understand this at first but this except helped a lot:
https://astrology-x-files.com/x-files/e ... astro.html

What is interesting is that the exaltation of the Nodes fall in the 12th and 6th houses respectively of the Thema Mundi. Now returning to the meaning of the astronomical scenario of the north node, this is showing that the Moon is in principle elevated in the 12th house, whereas the Selenic (lunar) principle is depressed in the 6th house. What this means is that the principle of incarnation in the physical world is elevated in the 12th, whereas you begin the process of leaving the physical realm in the 6th (sickness - Sagittarius) to rejoin in the spiritual where the Solar is elevated with the mind of Nous and realm of the etheric forms.

Virgo/Mercury => Libra/Saturn
-Mercury is exalted in Virgo and represents the idea of duality and helps Libra/Saturn in the process of fully realizing matter and separation.

Capricorn/Mars => Gemini/North Node
-Capricorn (representing death) is handing over to the 12th house which represents "pre-birth", thus linking the idea of death to incarnation in the physical world as described in the above excerpt.
-I suspect the Cancer/Sagittarius and Capricorn/Gemini pairs have their own logic with each other that exists in addition to how they fit into the broader schema.

As for the fixed signs, It was more difficult to describe these since the phases they represent are more abstract. I've tried to articulate their function the best I could though, below are the equal ascension pairs for the fixed signs:

Aquarius/Saturn => Taurus/the Moon
-Taurus symbolizes the initial stage of emanation from Aries/the Sun and Aquarius represents the last stage of emanation (before rejoining the source through Aries/Pisces).
-Aquarius/Saturn is dominating Taurus/the Moon; this suggests an intention to emanate anew even after re-merging with the source. The underlying meaning seems to be: "old endings and new beginnings".

Leo/the Sun => Scorpio/Mars
-Leo/the Sun (representing intent) symbolizes intense effort to bring about the full manifestation of matter as represented by Virgo/Libra while Scorpio represents the process of tearing down what is completed. Therefore the underlying meaning seems to be: "finish what was started and begin taking it apart again".

Lastly take the schema I've described and overlay it on top of the yinyang symbol. Imagine that phase #1/Aries is at the top of the white half of the yinyang symbol, phase #2/Cancer is on the left side, phase #3/Libra is located at the bottom of the black half and phase #4/Capricorn is on the right side. Recall that Cancer represents entrance into the visible world of matter and Capricorn represents leaving it, both suggesting borders between different modes of existence, just like the border in the yinyang symbol. Even more interesting is that the equal ascension sign pairs Cancer/Sagittarius and Capricorn/Gemini replicate the classic lopsided appearance of the separate yin and the yang components.

Regarding the fixed signs, consider the dominating planet for each equal ascension pair which is Aquarius/Saturn and Leo/the Sun. Each represents the opposite color dots in the yinyang symbol. Aquarius/Saturn (representing matter) is the black dot in the upper, spirit half of the Thema Mundi, meanwhile Leo/the Sun (representing spirit) is the white dot in the lower, matter half of it. The fixed signs seem to represent the "motivation" of the zodiac wheel, the engine within it that propels the endless cycle of becoming. Especially note that out of the four fixed signs, Taurus is the only one that has a planet exalted in it (the Moon, representing matter) and the domicile ruler of Taurus is Venus which represents desire; this suggests that the primary motivation for emanation is the desire to see spirit transformed into matter.

This schema shows the difference between the domicile signs of the Sun and Saturn and the exalted signs of these planets. The domicile signs represent a subsidiary active role while the exalted signs represent a more passive, overarching conceptual role. Also I want to clarify the difference between the zodiac wheel and the Thema Mundi. The zodiac wheel (beginning with Aries) represents the zodiac as a pure abstract archetype while the Thema Mundi represents the zodiac as understood from a terrestrial perspective (that is, incarnated into matter). This sounds obvious now but without the previous context it's hard to understand the difference.

Hello,

Interesting excursions into, what I would call, the depths of philosophy of astrology...

I myself am always into having personal projects on astrology e.g. currently I am compiling textual references and my own thinking on the paradigmatic significations of the zodiac signs, planets and houses through rational means and other stuff and this kind of work always interests me very much.

One question, though: Whenever we embark on a "project" like this, I'm fairly certain that you have one or more objectives you're aiming to fulfill. I am wondering what those are.

Forgive me for the overly technical presentation, hopefully you'll find the theory interesting enough to slog through the details.

No problem. Any philosophical excursion into explaining the “apparent many??? using the abstract few has to involve a lot of technical and rational exercise!

The "Taijitu" (AKA the yinyang symbol) is a representation of the relationship between the opposing forces of yin and yang. The zodiac wheel has a similar meaning and the concepts of yin/yang seem identical to the Platonic spirit/matter schema:

Maybe I am simplifying but the yingyang concept is the description of one of the "spiritual laws". In the case of astrology we are also applying the law of signature (aka law of correspondence, “As Above, So Below???). For the law of polarity, it mainly refers to the Pythagorean duality of the "other" for the "one" is not even describable (at least according to Parmenides). Ten of the pairs of polarity (a/t Aristotle, taken from Pythagoras) are finite-infinite, odd-even, one-many, male-female, right-left, rest-motion, straight-crooked, light-darkness, good-evil and square-oblong = summarized by the yinyang principle. Looking at the pairs, we can surmise that odd signs are masculine, even signs are feminine, diurnal signs are individualized (“one???) while nocturnal signs are public (“many???), some signs are straight and some signs are crooked, and so on, and so forth – BUT these are for the material manifestation (lowest hierarchy) of the wheel (highest hierarchy).

The zodiac wheel represents the cyclical process of spirit turning into matter and matter turning back into spirit. This can be described in four phases:

My opinion: I don’t think we should give matter/spirit assignment to each sign alternatively. Rather, all signs have their material and spiritual counterparts just like all signs (or planets) shall have universal (usually more abstract, soul like) significations and topical (usually more tangible or topical) significations.

One query: When you use the term emanation, are you referring to Plotinus’ (and his followers) theory? If so, then the emanation (as far as I know) refers to unidirectional of emanations from the “One??? (highest) down a series of further and further from the "One" to the lowest which is the so called “reality??? we live in. However, the mutual flow (Tao) of yinyang principle is definitely applicable to the Pythagorean pairs.

Also I want to clarify the difference between the zodiac wheel and the Thema Mundi. The zodiac wheel (beginning with Aries) represents the zodiac as a pure abstract archetype while the Thema Mundi represents the zodiac as understood from a terrestrial perspective (that is, incarnated into matter).

Thema Mundi = zodiac as understood from a terrestrial perspective… totally agree as the thema mundi requires ascendant, and anything that requires ascendant is sort of connected to the terrestrial.
Zodiac wheel (beginning with Aries) = the zodiac as a pure abstract archetype… totally agree but with the signs being all spiritual at the highest sphere but are matter when it is made the thema mundi. In fact, some of the Arabian/Persian astrologers refer to the Zodiac Wheel (not the constellation, just the mathematical abstraction of the zodiac wheel) as the highest intelligible sphere:
Highest Intelligible sphere: Zodiac Wheel (mathematical abstraction) followed by
Sphere of the fixed stars followed by
Spheres of the planets according to the Chaldean Order followed by
The sublunary spheres of the elements (Fire, Air, Water, Earth).

The above are just my opinion - and I may change them as opinions are neither knowledge nor truth!

Thank you for sharing and I strongly believe that astrologers should do this more...

@astrojin

One question, though: Whenever we embark on a "project" like this, I'm fairly certain that you have one or more objectives you're aiming to fulfill. I am wondering what those are.

My musings in this post are a byproduct of my deeper research into the connections between Christianity and astrology. Originally I noticed the similarities between old paintings of Jesus surrounded by the zodiac and the Buddhist bhavachakra paintings which made me curious if they were saying the same thing and what this implied for Christianity. I now believe they have a similar meaning; in fact, the "12 nidanas" that form the outer rim of the bhavachakra seem roughly equivalent to the twelve signs of the zodiac. It's not a 1:1 match but the same concepts are there, except in a different order(?). Alternately the order is the same but the Buddhists through their own cultural lens perceived the universal concepts underlying the twelve sign zodiac in a different way that only initially sounds unfamiliar. I freely admit that I'm speculating as a layperson though. I need to more deeply familiarize myself with the twelve nidanas so I can systematically hash out the differences between them and the twelve zodiac signs.

My opinion: I don’t think we should give matter/spirit assignment to each sign alternatively. Rather, all signs have their material and spiritual counterparts just like all signs (or planets) shall have universal (usually more abstract, soul like) significations and topical (usually more tangible or topical) significations.

I definitely agree with you that each sign has a separate matter/spirit manifestation and isn't purely matter or spiritual, I should have been more explicit about that haha. Mainly I was trying to propose a high level abstract mapping of the zodiac logic but I often slipped out of abstraction and referred to more concrete manifestations, although OTOH maybe this was unavoidable since I was using the Thema Mundi as a reference point.

One query: When you use the term emanation, are you referring to Plotinus’ (and his followers) theory? If so, then the emanation (as far as I know) refers to unidirectional of emanations from the “One??? (highest) down a series of further and further from the "One" to the lowest which is the so called “reality??? we live in. However, the mutual flow (Tao) of yinyang principle is definitely applicable to the Pythagorean pairs.

No, I was referring to the Platonic emanation and return theory. Although I was mostly using emanation in a descriptive sense, I just needed to express the "emerging" of something from something else.

It's nice getting feedback from someone very knowledgeable about philosophy, I know a smattering of things but it's not systematic or deep. One random question while I have your attention, can you articulate the difference between matter as represented by the Moon and how it's represented by Saturn? I get the impression the Moon represents actual matter while Saturn represents more of an "attitude" or abstraction about matter. There's a lot of interplay between these and I'm trying to improve my understanding of the difference.

Hello,

Thank you for the prompt response and feedback…

Before I could answer your question, let me explain a little bit of my take on universal vs. specific, and topical vs. non-topical in the context of significations in my astrological framework and practices. Now, I have to apologize for going too technical… hehe

Universal vs. Specific significations:
We all know that when a planet is used as a significator without association with the native’s house or lot, it becomes a universal significator.
When a planet as a lord of certain house or Lot (or when it is in a house or Lot) is used as a significator, then it is a specific significator for that particular chart.
Some astrologers simply drop the use of universal significators because they are not, by definition, specific enough but the ancients did place provisions for the use of universal significators upon certain qualifications.

Non-Topical vs. Topical significations:
It is also fruitful to segregate the non-topical from the topical significations.
Non-topical significations refer to significations that are abstract e.g. principles of severance, union, individuation, etc., wisdom, spiritual, etc.
Topical significations refer to significations that are tangible in the world (mundane astrology) and native’s life (natal astrology) e.g. illness, wealth, marriage, siblings, etc.

In combination, we would have universal topical & non-topical significators and specific topical & non-topical significators. Examples:
Venus as universal non-topical significator: principle of union, reconciliation and sharing (because Venus is the only planet that shares rulership with the three signs she is domicile or exalted ruler of), bringer of good news/fortunes/pleasures (because Venus is lesser benefic).

Venus as universal topical significator: the universal non-topical principle of union manifests itself as universal topical significator of marriage, association, acquaintances, healer of wounds, etc. The universal non-topical signification of bringer of fortunes/pleasures manifests itself as universal topical significator of bodily pleasures (as opposed to spiritual pleasure signified by the superior benefic Jupiter), love (passion), etc.

Any planet as ruler of the ninth house is capable of being the specific significator of matters concerning ninth house:
Specific non-topical signification of ninth house: wisdom, dreams, spiritual traveling/wanderings
Specific topical signification of ninth house: native’s higher learning academic achievements, religious station, physical journey/pilgrimage.

Observe that non-topical significations are more abstract whereas topical significations are usually more tangible and mundane related.

Non-topical meanings are always used even when delineating matters that are not topically related to that planet.
Imagine a chart that has Saturn as the specific topical significator of the father and Mars as specific topical significator of wealth, while Mars is in opposition to Saturn. When delineating the topic of father, we would say that the father shall suffer certain loss e.g. his life partially wasted (because Saturn being specific topical significator of father is in opposition to Mars whose non-topical signification is severance). In addition, when delineating the topic of wealth in the same chart, we would say that the native’s wealth shall suffer deterioration and corruption in some part of his life (because Mars being specific topical significator of wealth is in opposition to Saturn whose non-topical signification is slow deterioration or corruption). In both cases, I take the negative delineation due to the opposition aspect ceteris paribus. As all planets and all houses have both topical and non-topical significations, both significations are used but delineated differently based on contexts & settings.

Now we come to the matter & spiritual manifestation of the planets (or even houses). My take: The non-topical significations are usually inclined towards the spiritual whereas topical significations are inclined towards the matter. However, I am not going to say that this is an absolute position of mine!

The luminaries (sun and moon) are paradigmatic of the complementary pair of spirit & matter. Sun being the “true light giver”, the spark of light/live, is paradigmatic of spirit whereas Moon being the “vessel”, the body that receives, collects and distributes light, is paradigmatic of matter. The non-luminaries i.e. the other 5 planets partake both the spiritual and matter significations [with Jupiter and Saturn inclined towards more spiritual as they are sect mates of Sun whereas Mars and Venus inclined towards matter as they are sect mates of Moon].

The matter significations of Moon and Saturn:
Now to your question…(are you still reading … haha):

As mentioned above Moon is paradigmatic of matter and Saturn (when it is manifesting its matter principle) are really very different from Moon. Moon is paradigmatic of matter whereas Saturn is more inclined towards non-matter as he is sect mate of Sun. Moon is the lowest in the Chaldean order (also heavenly spheres) and fastest whereas Saturn is the highest and slowest. Moon is inferior whereas Saturn is Superior. Moon is life giving (like sun) because it is a luminary whereas Saturn is anti-life - Saturn is anti-life because Saturn is the furthest from the lights (luminaries) and also Saturn rules signs (Cap and Aqu) that are furthest from the signs ruled by the luminaries (Can and Leo); even exalted rulers of Ari and Lib are Sun and Saturn opposite to one another, and so on and so forth.

To wit, my speculation is that the matter manifestation of Saturn would be at the opposite end of the spectrum of matter to the moon. Analogy of Sun/Moon – Saturn… Superman’s x-ray vision, electromagnetic radiation (and even the eyes) are analogous to sun/moon but they can be easily blocked by lead (metal signified by Saturn!).

Examples of universal significations of Moon and Saturn:
Non-topical signification of Moon: changes and keeps on changing, renewals (she is the fastest and does not retrograde whereas the planet of change Mercury changes back and forth due to him having retrograde motion).
Related Topical signification of Moon: Latest Gen (Gen Z), top note (being fastest to evaporate)

Non-topical signification of Saturn: resistance to change, the past and forgotten
Related Topical signification of Saturn: gen O (O = old men/women... HAHAHA), the ancestors, the base note (being last to evaporate)

Non-topical signification of Moon: flowing (due to its quick motion and collecting & transferring light)
Related Topical signification of Moon: assets of highest liquidity (e.g. cash)

Non-topical signification of Saturn: immovable (slowest and "heaviest")
Related Topical signification of Saturn: assets of lowest liquidity (e.g. fixed assets, land, etc.)

Non-topical signification of Moon: beginning, initiation (door to the heavenly above as well as ruler of ascendant of the thema mundi)
Related Topical signification of Moon: life and livelihood

Non-topical signification of Saturn: the end, termination (the limits of the seven planets being the furthest planetary sphere as well as ruler of seventh and eighth of the thema mundi)
Related Topical signification of Saturn: death

How do we use these to isolate the material and spiritual significations of Moon and Saturn? Hmmm…

I don’t know whether the above discussion answers even part of your question but I am sure it will generate even more questions!

astrojin

i have read your reply.. i like how you are able to articulate things so well... i still feel this topic is more suited to the philosophy section, but regardless i would like to offering my own insights on something you mentioned... i think the way symbolism works is subjective in nature and i believe that each person processes the symbolism in their own way.. it is not static and meant to be thought of one way only.. but perhaps this is just me..

sun - spirit and moon - matter..
i think the polarity is more with sun and saturn... the moon acts as some type of intermediary..

i think of the moon as 'soul' here is the meaning from a dictionary that i think applies here - "A part of humans regarded as immaterial, immortal, separable from the body at death, capable of moral judgment, and susceptible to happiness or misery in a future state." in this regard it is like an individual flicker of light connected directly to the greater spirit that permeates everything.

in studying indian astrology, i was presented with the idea of the sun as a mild type of malefic... this idea was new to me, as i hadn't thought of it this way before.. i don't know the rationale for how they define benefics and malefics, but if a malefic, it doesn't really connect symbolically with the idea of the sun as pure spirit only..

i think of saturn as some form of karma, so the relationship with the moon is important.. its relationship with the sun is also very important.. how do we get rid of the accumulated karma over many life times? it is possible to turn saturn from lead to gold, but few know of how to do this.. time is a huge factor!

that's it! to steal one of your lines - hopefully you made it this far! cheers james

Astrojin, I appreciate your schema for universal topical & non-topical significators and specific topical & non-topical significators. I need to adopt the same highly systematic approach towards interpretation. I mean, I do to a degree but I haven't formalized it in my mind in this way. I feel like if I did then my interpretation skills would benefit a lot.

Now we come to the matter & spiritual manifestation of the planets (or even houses). My take: The non-topical significations are usually inclined towards the spiritual whereas topical significations are inclined towards the matter. However, I am not going to say that this is an absolute position of mine!

The luminaries (sun and moon) are paradigmatic of the complementary pair of spirit & matter. Sun being the “true light giver”, the spark of light/live, is paradigmatic of spirit whereas Moon being the “vessel”, the body that receives, collects and distributes light, is paradigmatic of matter. The non-luminaries i.e. the other 5 planets partake both the spiritual and matter significations [with Jupiter and Saturn inclined towards more spiritual as they are sect mates of Sun whereas Mars and Venus inclined towards matter as they are sect mates of Moon].

Wonderful insights, especially the difference in how non-topical/topical significations generally play out. If I may add, it's interesting to note that the two planets representing matter (the Moon and Saturn) both have their exaltations in Venus ruled signs and falls in Mars ruled signs, which closely correlates with what you're saying.

Your list of significations for the Moon and Saturn was very helpful, I learned a few new ones and the juxtaposition of the Moon vs Saturn helped clarify my existing knowledge as well. It also helped get me on the right track towards better explaining this issue. After reading your post I reviewed my old notes from the Schmidt course, cogitated on everything for a few hours and now I have an improved model to describe the difference between the Moon and Saturn as it relates to matter. In no particular order I'm going to list out the important points and afterwards I'll sum up their meaning. BTW for the sake of helping other readers follow along I'm going to be extra meticulous in my explanations:

*The quality of spirit (as represented by the Sun) is invisible and formless. This suggests that its antithesis matter (as represented by Saturn) is visible and has a form. In order for something to have its own shape this implies separation, as opposed to spirit which is unified and whole, there is nothing outside of spirit since it exists beyond time and space. In the material realm, everything is apparently separate and has its own shape and boundaries. You can experience separateness but you can't directly "touch" or isolate it since it exists as an inherent quality of matter. This suggests a certain abstract quality to Saturn, which aligns with your observation that Saturn has a more spirit-like essence.

*The Chaldean order of the Moon and Saturn is crucial to understanding how they differently represent matter. I was previously aware of this but I couldn't satisfactorily articulate it at the time. To be more explicit, the Moon is the fastest planet and casts a forward applying aspect while Saturn is the slowest planet and casts a forward aspect like any other planet, but it's not an applying aspect. What this symbolically represents is that the Moon is able to see "within" other planets intelligibly while Saturn can't see intelligibly and only sees an object/the external appearance. A mundane example using a dog is that the Moon sees the dog as an individual entity with its own identity ("Its name is Rex, it's five years old, it loves Doritos etc") while Saturn sees the dog as just a dog, no identity, just a fungible entity. This is the basic way that Schmidt described the difference between the Moon and Saturn.
-This secondarily suggests that the Moon is closer to the role of the true observer while Saturn is closer to the idea of what's being observed. The Moon really sees things and understands them, Saturn doesn't most of the time (when it's direct in motion) which represents this idea of "dumb" inert reality. This is appropriate because the Moon which represents the body carries the light of the Sun which represents spirit/mind. So the Moon could symbolize our "avatar" while we're in the world of matter while Saturn represents our environment.

*The world of forms is eternal and unchanging, the world of matter is temporary and constantly changing. Birth and death only happen in the material realm, which is represented by the Moon and Saturn. So the Moon and Saturn are representing different aspects of material existence as implied in your previous response.
-There are two beginnings of life and also two endings of it. The true beginning of life is spirit acting as the source of all things and represented by the Sun. The more mundane beginning (physical life) is birth as represented by the Moon. The true ending/antithesis of "life" (as the noetic source) is Saturn acting as the full manifestation of separateness and matter, meanwhile the more mundane ending is physical death also represented by Saturn. So both kinds of life are represented by the Sun and the Moon respectively while both kinds of death are represented by Saturn only. On that note, I recall reading that in ancient Egypt they often used the metaphor of death/imprisonment to describe the condition of physical life itself while true life is in the spiritual realm which is exactly the sense of life and death I was just referring to.

*In the material realm, life begins with the creation of a physical body, therefore matter and life are fully intertwined. However, death is not intrinsically connected to the existence of the physical body in the same way that life is. By that I mean that when you die your body doesn't instantly dematerialize (in most cases ), rather it continues to exist for awhile. This means that death is intangible in a way that life is not. Life is contingent upon the generation of a physical body while death is not.
-This probably explains why the Moon represents the body and physical tangible goods; anything that can be touched, held, etc; it's describing matter in a more tangible way. This is fully congruent with what the Lot of Fortune represents as well, being of course the lot of the Moon.
-Saturn OTOH describes matter in a very inverse way. Whether you're talking about metaphysical separation or physical death, in both cases you can't touch the absence of unity/life, you can only detect it, thus it's quite abstract in this sense which again supports your prior observation that Saturn is more spirit-like.

In conclusion, I believe my original stance of the Moon representing tangible matter and Saturn representing something more abstract was basically correct but undeveloped. I suppose when it comes to differentiating between matter as defined by these two we have to determine the context. As a general rubric, I would use the Moon to talk about the generation of matter while I would use Saturn to talk about matter in a general, metaphysical sense or when talking about the ending of matter. This makes sense, especially since Saturn also rules over time which is an intrinsic component of the material realm and is ironically more frequently associated with death than life.

I also want to clarify what the spirit to matter cycle means in practical terms. This was something I was previously confused about but I understand it better now. Basically, if Cancer indicates physical incarnation then what about Libra which represents an even more complete form of material manifestation? Aren't people fully manifested in the material world when they're born? To this I say that Libra (as representing the Aries/Libra axis, thus the spirit manifestation of Saturn) suggests an intangible attitude/orientation towards matter as opposed to the physical manifestation of it which is represented by the Cancer/Capricorn axis. There's a point in everyone's life where they fully differentiate between themselves and others which is the full realization of separation as represented by Libra. Of course, in a different context it can still refer to matter in a broad abstract sense.

EDIT: I realized I left out an explanation for the Leo/Aquarius axis. As mentioned in the OP, the fixed signs have a certain quality which I can't fully articulate at the moment. I can however reasonably deduce its role by considering the overall logic of the Thema Mundi:
-The Aries/Libra axis separates it vertically going from top to bottom (spirit to matter)
-The Cancer/Capricorn axis separates its horizontally going from left to right (birth to death)
-The Sun's exaltation Aries precedes the Moon's exaltation Taurus, however the Moon's domicile Cancer precedes the Sun's domicile Leo which is a reversal of what we see with the exaltations. If I interpret Taurus/Moon as representing the beginning of the emanation process (thus implying dependence on Aries/Sun) this in turn suggests that Leo/Sun is dependent on Cancer/Moon. If Cancer/Moon represents induction in the material realm then Leo/Sun implies something limited to that realm. My highly educated guess is that Leo/Sun is representing our actions in the material realm which end up affecting us later in the spiritual realm, so something like karma. I'm basing this on Valen's association of the Sun with praxis and Saturn with "nemesis" (nemesis is derived from Greek religion and represents the idea of receiving equivalent consequences for actions. I'm no expert on ancient Greek religion but I assume I'm correctly understanding Valen's reference here since it perfectly compliments what praxis represents). The Leo/Aquarius axis itself seems to reflect this since it traverses the Thema Mundi from the matter half into the spirit half. I still fully admit my reasoning is speculative but I think it's quite persuasive.

One last observation. During this discussion I realized I was often perceiving the Thema Mundi in spatial terms and crisscrossing that with a more metaphorical interpretation. That is, understanding the MC/Aries as the literal highest point in the sky while seeing the IC/Libra as a point deep in the earth. However, if understood metaphorically then Libra no longer represents being in the literal ground but rather the abstract concept of full material existence. This is interesting because Hell is usually perceived as a place deep in the Earth (reflecting the spatial understanding of the Thema Mundi), but if we use the metaphorical one then it suggests that Hell is material physical existence (or perhaps a state of mind). My intention isn't to be melodramatic, rather I bring that up because various esoteric religious groups have said something similar to that effect. It's interesting how both conceptions of Hell are so elegantly represented by the Thema Mundi.