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Nonphysical entities that exist in the mental or astral plane and are created purely from thought. Every thought generates vibrations in the aura's mental body, which assumes a floating form and colors depending on the nature and intensity of the thought. These thought-forms are usually seen by clairvoyants and may be intuitively sensed by others. Theosophists and clairvoyants place thought-forms in three classifications: the image of the thinker; an image of material object associated with the thought; and an independent image expressing the inherent qualities of the thought. Thoughts of a low nature, such as anger, hate, lust and greed create thought-forms that are dense in color and form. Thoughts of a more spiritual nature generate forms possessing a greater purity, clarity and refinement.
Thought-forms can be directed towards anyone, but to be effective they must latch onto similar vibration form the other person's aura. If they are unable to do so, they can boomerang back to the sender. Thus, one who directs evil toward another runs the risk of having it return.
Tulpas, also known as thoughtforms are frequently used in ceremonial or chaos magick.
A physical materialization of a thought, resulting in the creation of a being or object.
A tulpa is the given name to anything formed through the meditation (focusing) of an idea. The theory is that if you meditate hard enough on an idea, it will materialize. Tibetan monks practice this often, and teach it as part of their learning. Tulpa do not have to be live-creatures but can also be inanimate objects, animals, furniture, or creatures. There is a theory that the entire universe was made through tulpa meditation.
A tulpa is hard to define, as anything could possibly be a tulpa. While the idea is still being focused on, the object or creature may change & morph into different forms as the idea itself changes. Tulpa can only be destroyed by eliminating the thought (if the tulpa is not yet formed properly), or the diluting the concentration of the thought, then destroying the object or creature.
Interestingly, Mordechai Murdoch appeared to fit standard chaos magick practice for accidental creation of a 'Servitor' from a sigil, and appeared to be working its way up to an 'Egregore' (see: The Fluid Continuum).
A tulpa has been theorized as the cause of a case by Sam and Dean on three subsequent occasions. The first being in 8.08 Hunteri Heroici, when cartoon physics begin to manifest in the real world; it is later revealed to be due to a elderly psychokinetic by the name of Fred Jones who had begun to lose control of his abilities because of his deteriorating cognitive faculties. The second incident was during 9.15 #THINMAN when Dean accuses the Ghostfacers of cooking up the legend of Thinman with a tulpa. Finally, in 10.05 Fan Fiction, the Greek goddess Calliope conjured a scarecrow which Dean assumed to be a tulpa brought upon by a Supernatural play's dedicated contributors. – Pad of Definitions (1.06 Skin (episode)), Official Website