The Alignment
I've seen a few different theories, but I believe that this is how the Chinese zodiac rightly fits onto the circle of signs:
Aries - yang air - horse
Taurus - yin metal - hare
Gemini - yang earth - dragon
Cancer - yin earth - rat
Leo - yang fire - ox
Virgo - yin wood - snake
Libra - yang metal - tiger
Scorpio - yin fire - ram
Sagittarius - yang water - boar
Capricorn - yin air - rooster
Aquarius - yang wood - monkey
Pisces - yin water - dog
I am aware that there are only 5 elements in Chinese astrology, but seeing that there are 12 animals, each with a yin and a yang, I think the sixth element got lost somewhere over the centuries.
After aligning the animals and elements as individual pieces to the astrological circle, I also think that the animals are paired up with the wrong elements in the traditional Chinese Zodiac. I wrote what I believe to be correct.
On the western end, this theory allows six elements instead of four with two signs per element.
The way that I came by my element and animal associations is by using the site http://www.turtleluck.com/main-elements/ . I read all the element descriptions: yang wood, yin fire, etc. and I read some descriptions of the western sun signs and matched them up according to things they had in common. The yin and yang air signs were left over, and when I looked at the description of Capricorn it mentioned a 'rarefied air' that is a signature to the sign. That rarefied air means high prestige. The sign is also the mid-heaven, and heaven is associated with the sky and air. I decided that it was fit for air. Finally, the rooster sign fit Capricorn through the animal's description on turtlelluck.com and through the method that I will describe further down in this post. It makes sense that the bird sign is an air sign. Similarly, it makes sense that the monkey sign is a tree sign in Aquarius! If you look at all the elements when on the circle, you will see that yang signs always oppose yang signs, and yin signs always oppose yin signs.
The animals were tricky. I was lucky enough to already have 4 of them in the right position so that I could discover a pattern that I used to place the rest of the animals, and it lined up perfectly. Monkey lined up with a tree, the dragon lined up with the mountain, which emphasizes hugeness as a major trait. Pig lined up with yang water and is famous in the saying "sweat like a pig." Sweat is yang water! All these intuitive associations were present after applying the method that I'll describe.
The four animals that I had correctly placed were: rat in cancer, ox in Leo, tiger in libra, and hare in Taurus. All the rest were incorrect. For the longest time, I had dog associated with Aquarius. At some point, I decided to look for inspiration in the Chinese Zodiac story of the Great animal race. After an eternity of grappling with the alignments, this was the first time that I consulted the story. Luckily enough for me, the animals that I had correct were the first four finishers in the story of the race, and this revealed a pattern for the rankings of the animals in the story.
In the story, the animals finished the race in this order from first place to last place: rat, ox, tiger, hare, dragon, snake, horse, ram, monkey, rooster, dog and pig.
The first part of the pattern is this: take the planet exalted in the chosen sign, it represents the zodiac animal. For example, moon in Taurus represents the rat! The reason is that rat is associated with cancer and the moon is the ruler of cancer. So in other words, the moon is the rat and it is exalted in Taurus.
The second part of the pattern is this: start with the moon in Taurus and, going clockwise, touch upon all the exalted planets in the signs. You will discover that the order of the planets is the same as the order of the rankings of the zodiac animals in the race. The planet that is associated with the animal determines the sign that is associated with the animal; sometimes it is in a definite manner and sometimes it narrows it down to a 50/50 about where the animal should be associated.
Like I said before, I was lucky to have the first four finishers of the race in the correct signs. So, I just happened to notice that rat ruled cancer, and relatedly, the moon is exalted in Taurus. Going clockwise, the next exalted planet is the sun in Aries. The ox was associated with Leo, so the sun in Aries represented the ox who placed second in the great zodiac race. The next exalted planet is venus in Pisces. Venus rules two signs: Taurus and libra. So, the next two animals to finish in the race would be associated with these two signs. The two animals were the tiger and the hare. I already had the tiger associated with libra and the hare associated with Taurus!
This pattern made it clear to me that all I had to do was continue going clockwise and evaluate the exalted planet to see which animal belonged in the associated sign. All the rest of my animal placements were wrong up to this point. As the next exalted planet was mercury in Aquarius, the signs of Gemini and Virgo were now on the table. The next animals in the rankings were dragon and snake. I had it narrowed down to 50/50. Dragon would be either Gemini or Virgo, and snake would take the other sign. I looked at the element that I already had associated with Gemini and it was yang earth. This was symbolized by the mountain and was noted by hugeness. The hugest animal in the zodiac is the dragon. With this kind of reasoning and a good reading through of the sign, the element and animal description, I settled with dragon in Gemini and this left snake to Virgo. Snake in Virgo fit well as the snake was described as a healer and fast calculator. Both of these traits were of Virgo.
The next planet was mars in Capricorn. Mars also rules two signs. The next animals were horse and ram. I settled on horse for Aries and ram for Scorpio.
Mars is exalted again in Sagittarius, but I just skipped over that because mars was complete.
The next exalted planet was uranus in Scorpio. The next animal was the monkey. This placed monkey to Aquarius.
The next exalted planet was saturn in libra. Aquarius was already done, so only Capricorn was left of the two signs ruled by saturn. The next animal was the rooster and this placed rooster in Capricorn. The bird went to the heavens!
Mercury in Virgo was already done with.
Neptune in Leo was very specific to Pisces as neptune rules Pisces alone, and the next animal was the dog, thus dog was associated with Pisces.
Lastly was jupiter in cancer, the last animal was the boar and the only sign left was Sagittarius.
Thank you.