El Sri Yantra.
The Sanskrit word yantra comes from the prefix yan, which means to conceive and by antonomasia, mental conception. Yantra, then, literally means "device", "artifice", "mechanism", "tool" or, more precisely, "instrument". It refers to complex geometric representations of levels and energies of the cosmos (personalized in the form of a chosen deity) and of the human body (insofar as it is conceived as a microcosmic replica of the macrocosm).
The yantra is completely interiorized in the highest levels of the tantric ritual, through the mental construction of a complex geometric model and its visualization. Once built mentally, the yogi gradually dissolves it (laya). The yantras are built from inside to outside or from outside to inside, depending on the geometric figure in which the yogi thinks. The yogi manages to identify himself completely with the chosen figure to the point of not differentiating if the Yantra is inside him or is he who enters the Yantra.
The practitioners of this kind of mental exercises of yoga affirm that, if done successfully, this exercise will catapult the practitioner towards pure consciousness (sâdhaka), beyond the distinction between subject and object.
A large number of yantras are used in Tantra. The most famous of all is the Sri Yantra which is composed of nine triangles juxtaposed and placed so that they give rise to 43 small triangles. Four of the first nine triangles are oriented upwards and symbolically represent the male cosmic energy Śivá; the other five triangles are oriented downwards and represent the female force Śakti. These triangles are surrounded by an eight-petalled lotus that symbolizes Vishnu. Wrapping it, a sixteen-petalled lotus represents the power of the yogi over the mind and senses. Enclosing this lotus are four concentric lines that connect symbolically with the two lotuses. The triple line that surrounds it designates the analogy between the entire universe and the human body. Bibliography
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