The first thing we would like to specify is the advice that this article is devoted to Cait Sith but not to Reeve. Such aspects as Reeve's motives and features of his character are not reviewed here. This article is a try to define the nature of Cait Sith, what it is or who he is, is he a living being or a marionette doll. Unfortunately, when it is required to refer to mythology or similar sciences to make some issue clear, the Internet or amateur magazines can't give you comprehensive information, and those who refer to such unreliable sources are fated to spread patently false data further and further. If we randomly choose five texts where Cait Sith and Celtic mythology are mentioned, we will be able to see that every article insists on its own version but can't give a coherent, logic substantiation of its thesises.

Let's start from basic information about Cait Sith to remember some details to draw analogies to it later.
What we know about Cait Sith:

• it is a stuffed toy in the form of a cat (cat-toy).
• it has too big ears for a regular cat.
• its face keeps friendly expression, eyes are always closed.
• it has crown on its head.
• it wears red cape.

Cait Sith's objectives:

• collecting and transferring information; being there, where Reeve or his allies can't be; mean of communication.
• mediator for expressing Reeve's thoughts and emotions, some kind of proxy between him and the outer world.
• metaphorical instrument for discovering personality without wasting time on the character taking its part in the narration.

Theories listed below don't have a logical base and represent a mix of something heard, seen, read, misunderstood or wrongly translated.

:: It is a robot, plush skin filled with electronics. Reeve controls the robot from Shin-Ra HQ using joystick.
Cait Sith isn't a robot, he hasn't drives, cameras and schemas inside. Thus, he needs a vehicle or a foothold. We can see that Cait Sith is able to move his head and pads but he hasn't a locomotor system, so he isn't up to carry out complex movements like walking, climbing or jumping. It is clearly seen in AC when Cait Sith falls from RedXIII's back and can't turn in right direction. Also in the final scene of AC we can see Marlene holding Cait Sith in her hands, and on the group photo of Cloud party we see that Cait Sith is trying to kick RedXIII. That is Cait Sith can move but can't stand.
During the events in the Temple of the Ancients the fact that he can walk after falling from his moogle-shaped toysaurus and become able to climb on it becomes a discovery for him. On the other hand, while controlling Cait Sith with a joystick, Reeve always needs to spend time next to some monitor, managing robot's movements and don't looking aside on his immediate duties of the Head of Urban Development Department. In the scene of live broadcast from the conference in Shin-Ra HQ and in the episode of discussing Rufus's fate we see Reeve without any devices in his hands at the time as Cait Sith is moving during the events taking their places in parallel. The fact that Cait Sith is not equipped with a camera is confirmed by conversation with Marlene, taken by Reeve as if a hostage: Marlene reacts to a voice but not to a picture. In different episodes we see Cait Sith with PHS and hear how he mentions a word "overhear". It is logical to assert that Cait Sith is not able for broadcasting, otherwise this ability would certainly used or mentioned just for once. In that way we see that Cait Sith's technical abilities are very limited. What kind of robot would it be, if it doesn't use its mechanical advantages?

:: It is a sprit, summoned by Reeve with Summon Materia.
First, the period of existence and activity of the Summons is limited. Long autonomous existence of summoned creatures is impossible in the limits of the functioning rules of the Materia itself. Furthermore, during the Game we meet several Cait Siths. First Cait Sith we meet is in Honeybee Inn in the room occupied by Reeve's parents. The second one perishes in the Temple of the Ancients. The third one accompanies Cloud party till the end of the events. According to the principles Materia works on that would mean that Reeve has some Materia not presented among materias we can meet in the Game including even rarest natural born. One more questions to the Summon version is in what way Reeve gets information from the summoned spirit and uses it for broadcasting. In addition, at the time when party gathers before decisive battle Cait Sith is lifelessly flatted on its toysaurus and revives with apologies for delay in Midgar, that is we see a direct connection between Cait Sith and Reeve - Cait Sith can't move and speak while Reeve can't devote himself to its control.

:: It is an AI, Shin-Ra Company production. Reeve assails a reasonable being, forcing it to perform various actions...
The problem of AI and technologies giving the possibility of its existence are not covered in the Game. There is no any mention of Shin-Ra department researching or developing information technologies, and consequently, even in presence of its hypothetic existence it is not playing its part in the story. Furthermore, it seems strange that the one who is using AI is a man with a profession far removed from IT.

:: It is the mythic King of All Cats on Shin-Ra's duty.
The name "Cait Sith" or "Cat Sidhe" actually refers us to Celtic mythology. The image of a cat with a crown and in a red cape is widely spread in fairy tales and legends. However, if we try to find an analogy between Cait Sith and some mythic cat-like creature, we need to keep in mind that similar characters are also presented in the myths of other European and Slavic nations, so referring to only one culture is the wrong way for entire subintellection. Such interpretation of the character leads into a dead end. We can't suppose that Cait Sith is the mythic cat-like demon, because we know that it is a toy controlled by Reeve, but not the independent - living or ghost - being.

Cait Sith isn't a just fun feature to the story. He as an occurrence is important for understanding of the whole picture of the narration, for possibilities existing in the world generally and available for the characters of the story specifically, for the oblique discovering of one of the characters and for estimation of the concrete situation in the Temple of the Ancients. In that way, Celtic demon disappears from Shin-Ra staff, and the theory explained below can be considered as valid and viable from the standpoint of outspoken tasks. The basis of this theory is really Nord-European culture, but it only serves as a reference and as a starting point for forming of the conclusion "What kind of thing is Cait Sith".

A fantastic cat-like demon is more later occurrence than the theory expounded in details below; it is an echo of an original conception of Siths, an element of pop-culture. If we turn to mythology to as a science, we will be able to open an interesting material. Thus, an old Irish (and also British, German, Gallic and Scandinavian) legend says that in a village lived an old lady, and on her window-sill she has a lot of clay and woolen cat-like toys. All cats had closed eyes, big ears and sad faces. People of the settlement thought that every time a child died in the village, one more cat appeared on the window-sill and the witch got one more servant. "Cait" means "cat", "Sith" or "Sidhe" is "sanctuary", magic hill where human-like creatures - elves, fairies, forest spirits - lived in according to the legend. From the name of their dwell came their name, known in Gaelic language as "Aes Sidhe", that means "People of the Hills". Cait Sith is wrongly taken as a Sidhe dweller, some cat-like demon cat-like spirit, whereas it is a Sidhe itself. Cait Sidhe are ritual toys being created according to defined canons to enclose spirits in them. Spirits could be different - from spirits of died people to alfar. It was accepted as they could tell their owners different information - about missing things and people, about future weather, about events in far lands - and was able to tell the fortune.

Kind and respectful attitude to the spirit enclosed in a Sidhe brings luck and transforms a toy in a talisman able to help both in peaceful business and in battles. However, you was not allowed to ask from the spirit too much - it could show its capricious and even revengeful temper. Let's examine the canons of Sidhe creating and compare them with Cait Sith's figure. Eyes of Cait Sith always being made closed - a visual contact with a spirit was considered as fatal for a human. Ears being made disproportionately large - it was considered that it allows a spirit to hear as much and as long as possible. Often the summoners presented toys with cloaks, gloves or ornamentals. Face of Cait Sith could be sad, funny or thoughtful but always friendly and peaceful. It was supposed that kind spirit will avoid ugly, grimacing Sith, but evil, the opposite, will consider it as best sanctuary for itself and it is fraught with troubles for the summoner. These toys being made from materials easy to destroy (clay, wax, fluff), it was necessarily for making the spirit free if it's work was completed. In case of our Cait Sith this material most probably is plush. When Sith was destroyed, spirit gained freedom and went away to its world not obeying its owner anymore. Reeve's Cait Sith that is a sanctuary for his voice, and it is safe to say that the one who takes the part of the spirit of this Sith is Reeve himself.

How Reeve controls Cait Sith if we get rid of the idea about joystick? The most probable seems to be the idea about the Manipulate Materia that appears at the disposal of a player right after meeting with toy fortune teller. It allows Reeve to control Sith without any mechanical manipulator. The crown on Cait Sith's head usually associated with a part of the King of All Cats attribute is nothing else than Hypno Crown you can find in the Forgotten Capital. The effect of Hypno Crown is to "increase manipulate rate", and this accessory is logically coordinating linking to the basic Cait Sith's equipment. One more proof in the benefit of described theory about Sith as a shell, able to become a container for life, is the scene of Cait Sith's revive in the Temple of the Ancients. Sith had worked as it should, under the influence of the powers of the Temple some life source had settled itself into Cait Sith that had allowed him to discover himself as a personality. The puzzle in the Temple been solved not by Reeve. It was Cait Sith by himself.

In the Temple Reeve takes the only right decision: to solve a puzzle transforming the Temple by the pads of a toy that excludes the possibility of victims. Reeve is sure about the possibility of sacrificing one Cait Sith: there are many toys, and Reeve is in safety place, he doesn't come to harm with Sith's death. This episode calls for anger of the followers of the version about Cait Sith as a living being, and Reeve sends him to certain death. However, their holy wrath can be pacified - at the moment of taking the decision to solve the puzzle Cait Sith is a toy, a Sith of Reeve. Reeve have no any idea about that after few minutes Cait Sith will become someone alive and independent. Some living source inspired Cait Sith when it falls from toysaurus, and from this time Cait Sith becomes an individual consciousness. The newborn Cait Sith climbs on toysaurus with diffidence, disbelieving his feels. After that he moves and dances permanently as if he try to get as much pleasure as possible with his new gained abilities.

Cait Sith solves the puzzle in a few minutes, although he admits its complexity. Starting from that, we can suppose that life source settled into him is a small piece of the part of the Temple Aerith spoke with. We can assume it also by seeing how honored with the possibility to take his part in rescue the Planet Cait Sith is and how he doesn't try to avoid his task for the sake of saving his new substance. Going from the way of checked and confirmed by quotes facts we may say that Reeve probably was stunned, touched, and depressed watching on the actions of a living being named Cait Sith sacrificing itself and hearing its last words: "There's plenty of stuffed toys like my body around, but there's only one me!"

Creature discovered itself as Cait Sith disappeared with the Temple. Cait Sith #2 shown up right after is a toy Reeve's mediator again, acting under the Manipulate Materia effect. In a benefit of that is not a next summoned spirit, counts that this Cait Sith already knows each party member and understands their relationships, acting itself as a full party member. From this moment and until the end of the story Cait Sith takes again his allegoric part of a shell for the spirit belonging to the other body.

There is a popular parallel between Cait Sith's perish in the Temple of the Ancients and death of Aerith: Cait Sith's death is not considered as a tragedy because Cait Sith is easy to restore and his death emphasizes irretrievability of loss of Aerith. This parallel calls us to the gross statement that only decease of a man close to us is sorrow and loss, and we can easily sacrifice some unknown creature with stuffed body. In the light of worded facts this sentence has no ground. Furthermore, this unjust statement is dispelled right by Reeve during his jarring with Barret, so it is a mistake, to follow it as a thesis. If we would make a parallel between victim of Cait Sith and victim of Aerith, then this parallel rather be sound like "for the sake of saving the Planet courageously and selflessly sacrificing theirselves both the best from the people and little unnoticeable creatures". And you can't count in figures that someone's victim is bigger and someone's is smaller, you shouldn't forget no one small hero: "Don't forget me even if another Cait Sith comes along. Good bye..."