In ancient Egyptian religion, Ammit (also spelt Ammut and Ahemait, meaning Devourer or Bone Eater) was a femaledemon with a body that was part lion, hippopotamus and crocodile. A funerary deity, her titles included “Devourer of the Dead,” “Eater of Hearts,” and “Great of Death.” Ammit lived near the scales of justice in Duat, the Egyptian underworld. In the Hall of Two Truths, Anubis weighed the heart of a person against Ma'at, the goddess of truth, who was sometimes depicted symbolically as an ostrich feather. If the heart was judged to be not pure, Ammit would devour it, and the person undergoing judgement was not allowed to continue their voyage towards Osiris and immortality. Once Ammut swallowed the heart, the soul was believed to become restless forever; this was called "to die a second time". Ammit was also sometimes said to stand by a lake of fire. In some traditions, the unworthy hearts were cast into the fiery lake to be destroyed. Some scholars believe Ammit and the lake represent the same concept of destruction. Ammit was not worshipped, and was never regarded as a goddess; instead she embodied all that the Egyptians feared, threatening to bind them to eternal restlessness if they did not follow the principal of Ma'at. Ammit has been linked with the goddess Tawaret, who has a similar physical appearance and, as a companion of Bes, also protected others from evil.
In Egyptian mythology, Taweret (also spelled Taurt, Tuat, Taueret, Tuart, Ta-weret, Tawaret, and Taueret, and inGreek, Θουέρις "Thouéris" and Toeris) is the Egyptian Goddess of childbirth and fertility. The name "Taweret" means, "she who is great" or simply, "great one". When paired with another deity, she became the demon-wife of Apep, the original god of evil. Early during the Old Kingdom, the Egyptians saw female hippopotami as less aggressive than the males, and began to view their aggression as only protecting their young--not territorial, as was male aggression. Consequently, Taweret became seen, very early in Egyptian history, as a deity of protection in pregnancy and childbirth. As a protector, she often was shown with one arm resting on the sa symbol, which symbolized protection, and on occasion she carried an ankh, the symbol of life, or a knife, which would be used to threaten evil spirits. As the hippopotamus was associated with the Nile, these more positive ideas of Taweret allowed her to be seen as a goddess of the annual flooding of the Nile and the bountiful harvest that it brought. Ultimately, although only a household deity, since she was still considered the consort of Apep, Taweret was seen as one who protected against evil by restraining it.
Apep formed part of the more complex cosmic system resulting from the identification of Ra as Atum, i.e. the creation of Atum-Ra, and the subsequent merging of the Ogdoad and Ennead systems. Consequently, since Atum-Ra, who was later referred to simply as Ra, was the solar deity, bringer of light, and thus the upholder of Ma'at, Apep was viewed as the greatest enemy of Ra, and thus was given the title Enemy of Ra.
As the personification of all that was evil, Apep was seen as a giant snake/serpent, crocodile, or occasionally as a dragon in later years, leading to such titles as Serpent from the Nile and Evil Lizard. Some elaborations even said that he stretched 16yards in length and had a head made of flint. He is sometimes known as the “chaos snake.” Tales of Apep's battles against Ra were elaborated during the New Kingdom. Since nearly everyone can see that the sun is not attacked by a giant snake during the day, every day, storytellers said that Apep must lie just below the horizon. This appropriately made him a part of the underworld. In some stories Apep waited for Ra in a western mountain called Bakhu, where the sun set, and in others Apep lurked just before dawn, in the Tenth region of the Night. The wide range of Apep's possible location gained him the title World Encircler. It was thought that his terrifying roar would cause the underworld to rumble. Myths sometimes say that Apep was trapped there, because he had been the previous chief god and suffered a coup d'etat by Ra, or because he was evil and had been imprisoned.
The light is obviously some kind of essential energy of the earth which heals and renews life. The Island is the place which keeps life and death balanced. The ancient Egyptians found it at some point, so it was probably the origin of their legends of the underworld, because the souls of dead people are able to communicate with the living there. The Egyptians built the huge statue of the goddess Taweret, who was the goddess of motherhood and also the wife of Apep, the original god of evil. She was believed to protect the world by restraining Apep, who wanted to destroy it. The Egyptians must have seen the smoke monster and assumed that it was evil, creating the legend of Apep around it. In fact, it was merely chaotic, and it assumed the characteristics of the people it absorbed. The Egyptians probably built the cave and the pool/capstone, using the electromagnetic energy of the light/water to keep the smoke imprisoned. They did not understand the details of what they were doing, they just knew they had to protect the world from chaos. Since the light and darkness were probably in a natural balance when they found the Island, they may have inadvertently created an imbalance by tampering with it. By imprisoning the chaotic darkness, they caused it to build up like a pressure valve that has been blocked.
In later history, the crazy woman “Mother” came to the Island. She saw what was going on there, even though she didn’t fully understand it, and believed that she must protect the light at all costs. At some point, she was so entranced by the light that she went into the cave and entered the pool of water. She may even have removed the capstone and then replaced it. As a result, she died and was absorbed by the smoke monster. It took on parts of her personality, including her intense desire to protect the light from outsiders. When Jacob and his brother were born and “Mother” raised them as her adopted children, she was already dead. It was actually the smoke monster that raised them. The evidence of this is as follows: when Mother knocked out Jacob’s brother, she was somehow able to destroy the village, kill all the men, and fill in the well all by herself while he was unconscious. How else could she have done this unless she was the smoke monster? Also, she told Jacob never to go into the light because it was “a fate worse than death.” How could she have known what would happen unless she had seen it happen to someone else, specifically herself? When Jacob’s brother killed her, he stabbed her before she had a chance to speak to him; this is apparently the only way to kill the smoke monster when it is in human form. As a result, the smoke must have returned to the cave and been unable to roam around anymore. However, Jacob accidentally set it free again when he threw his brother into the cave.
This time, the smoke absorbed his brother’s personality, including his intense desire to leave the Island. It had probably never cared about leaving the Island before. Jacob saw this and dedicated his life to keeping his “brother” imprisoned, because he assumed (probably correctly) that the darkness was not meant to leave that place. If it did, the balance of life and death would be irrevocably destroyed and the whole world would die. (Interestingly, it was “Mother” who showed Jacob how to protect the light, which means the smoke monster was actually responsible for imprisoning itself. This is further proof that the darkness, being chaotic, did not have any inherent desires of its own. It merely took on the desires of people it absorbed. Since Mother wanted more than anything to protect the light, it showed Jacob how to do that.) Drinking the water that had been affected by the light gave Jacob near-immortality and a limited amount of power over the Island. Thus, he was able to make rules about what could and couldn’t happen there. The smoke monster was also able to make rules (remember “Mother” made it so Jacob and his brother couldn’t kill each other). So, they started their long game where Jacob tried to prove that people were inherently good and his “brother” tried to prove they weren’t. This was really just a continuation of the argument they had been having over the opinions given to them by “Mother.” The light and the darkness don’t actually care about good and evil; it was a construct imposed on them by Jacob and his brother.
Jacob brought all the candidates to the Island because he wanted a replacement. He was tired of the game. He didn’t know that he could have stopped it any time by entering the cave and becoming the smoke monster. Either that, or he did know but was afraid to. When Desmond removed the capstone, he did not die, and therefore he was not absorbed by the smoke. He thought that by removing the stone, he would open a bridge between the Island and the alternate reality which he could see parts of. What he didn’t realize was that the alternate reality was not actually real in the way he thought it was. It was a collective hallucination of all the dead souls who were waiting to move on. They all died at different times and in different places, but they all waited for each other in that dreamworld so that they could move on together. Clearly, Hugo, Ben, and the people who left the Island in the plane lived on long after Jack died in the bamboo grove. Hugo and Ben referred to the time they had spent together looking after the Island, saying “You were a great #2,” and “You were a great #1.” They must have lived for years after Jack’s death, as did the people who escaped in the plane (the same plane Jack saw fly over him as he was dying). The alternate reality was simply a waiting room where everyone gathered after their various individual deaths. It started out as a dream representation of Los Angeles and what would have happened if the plane hadn’t crashed. They were able to live there for a while and make the choices they should have made in life. However, after they all found each other, they remembered what really happened and how much they needed each other in order to let go and move on together. Some of them, like Ben and Anna Lucia and Michael, weren’t ready to move on, so they stayed behind to think about their lives some more. During their time in the dreamworld, they were able to appear on the Island in the real world in order to talk to those still living. This is because the Island acts as a gateway between life and death.
An interesting consequence of all this is that Jack most likely became the smoke monster after he died. However, he only “became” the smoke monster in the way that Jacob’s brother did. It’s more accurate to say that the smoke monster became him. It absorbed his personality and took on his characteristics. His physical body died and his soul moved on into the next world, but the construct of his personality merged with the smoke. This means that during Hugo and Ben’s time running the Island, the smoke monster was probably much nicer to people, much more reasonable, and much more caring. In fact, it was probably more of a smoke doctor.