Potent as it is, in tantric art the lotus is a symbol of the expanding consciousness, which ultimately raises the aspirant from the dark depths of ignorance to the radiant heights of inner awakening. Because of its smooth and oily surface the lotus is not affected by the water in which it grows. Hence just as the lotus plant grows in the 'darkness of mud' and gradually blossoms out to the surface of water, unsullied by the mud and water which nourishes it, so the inner-self transcends beyond its own material limits, uncorrupted and untarnished by illusion and ignorance.
The lotus blossom is one of the principal archetypal symbols used in yantras. Generally centered on the axis with its petals unfolding towards the circumference, it is the appropriate image to illustrate the unfolding of power of the divine essence. Because of its associations with progression, development and the life-expanding quality, the lotus represents the 'out-petalling' of the soul-flower in the process of spiritual realization. Hence in ancient cosmology, the lotus is also associated with creation myths. It is, for example, often depicted as springing from Vishnu's navel, supporting and giving birth to Brahma, the creator.
Brahma falls asleep, and the lotus closes and goes back into Vishnu's navel. Vishnu then sleeps on the serpent's coils. The process eventually begins all over again. The lotus hence here represents the unfolding of a new age (Yuga in Sanskrit); similarly in a yantra it signifies the awakening of the inner self. Since the earliest times, the lotus has always been a symbol of the citadel of the heart, the seat of the Self.
Yogis believe that there are actual spiritual centers within us whose essential nature and luminosity can be experienced during meditation. These spiritual centers are often represented symbolically as lotuses, and their 'opening up' implies the state of complete repose when the purpose of yogic meditation is attained.
In the final analysis, though a yantra is made up of different elements, the fundamental aim of ritual and meditation is to fuse all these dimensions, and to facilitate the adept's spiritual journey, as follows:
The outermost square sanctuary has a landing before each of its four gates. This is a two dimensional representation of a low flight of steps leading up from the ground to the raised floor of the sanctuary. This sanctuary is the seat of the divinity. This is exactly the model on which the Hindu temple is built. Hence each Hindu temple is a yantra in itself.
Once the spiritual seeker enters the square enclosure, and starts moving towards the center, the symbol of the flowering lotus represents the awakening of his/her inner consciousness to its maximum potential. As the journey progresses, the adept encounters the various aspects of manifestation inherent in nature, symbolized by the male and female principles (the triangles). These are bounded within a circle. This symbolizes that all reality is confined within these concepts. The journey towards the center encompasses both distance and the course of time. This space time continuum is represented by the straight line.
Finally the devotee reaches the center, the reservoir of all knowledge and the final goal of his journey. But the spiritual awareness generated within him during his penetration to the central essence makes him realize that this point is nothing but the center of his own heart, the innermost realm of his being. This realization is the ultimate aim of the yantra.
In Tantric thought the human body is visualized as a microcosm of the universe. It is believed that the complete drama of the universe is repeated in this very body. The whole body with its biological and psychological processes becomes an instrument through which the cosmic power reveals itself. According to tantric principles, all that exists in the universe must also exist in the individual body. If we can analyze one human being, we shall be able to analyze
the entire universe.
The purpose is to search for the whole truth within, so that one may realize one 's inner self, unfolding the basic reality of the universe.
A Tantra text says: "He who realizes the truth of the body can then come to know the truth of the universe'. The two most important concepts associated with the human body are the chakras and Kundalini. In addition to helping realize the abstract conceptions of Tantra in visual terms, they reveal to the spiritual seeker the deepest truths of Tantric philosophy through metaphors and symbols.

Tantra Yogic Philosophy recognizes seven energy centers in the human body. These are known as 'chakras'. Chakra means "what revolves" and hence signifies a wheel. In a physical sense the chakras are visualized as lotuses, composed of different number of petals. Each chakra governs a certain sense organ, and has its own presiding deity.
The Seven Chakras are:

Sahasra Padma Chakra: Sahasra in Sanskrit means thousand, and padma means lotus, this chakra hence is also known as "the thousand petalled lotus." It is located above the crown of the head. It is the meeting place of the Kundalini Shakti with Shiva. It governs the voluntary nervous system, and is said to be the seat of pure consciousness or ultimate bliss.
Ajna Chakra: Ajna means command, and this chakra is called the center of command as it is from here that the other chakras are guided. It is often called the Third Eye, and is located between the eyebrows. It is made up of forty-eight petals, and its presiding deity is Paramashiva. It rules over the mind as a sense organ.
Vishuddha Chakra: Vishuddha means "very pure", and as such this center is believed to very subtle. It is made up of sixteen petals, and the presiding deity is Ardhanarishvara. This chakra governs the organ of sound, the ears, and is located in the throat.

Anahata Chakra: Anahata means "unstuck sound", and it is from this chakra that the inner sounds or natural music of the body is said to arise. It is made up of twelve petals and is located along the spine at the level of the heart. Its presiding deity is believed to be Isha. It governs the organ of touch, the skin.

Manipura Chakra: Manipura means "the city of gems", and this chakra is thought to be radiant like a city of jewels. It is also called the 'navel' chakra since it is located behind the navel. It is made up of ten petals, and its presiding deity is Rudra. The Manipura chakra rules over the sense organ of
sight, the eyes.
Svadhishthana Chakra: In Sanskrit, Svadhishthana means self-abode. It is situated in the spine in the region just above the genitals, and is made up of six petals. This chakra governs the principle of taste, and its presiding deity is Lord Vishnu.
Muladhara Chakra: Muladhara means "root foundation", and is hence also known as the root chakra. It is located at the base of the spine. This chakra has four petals and rules the organ of smell, the nose. Its presiding deity is Brahma.
The Sanskrit word kundalini means 'coiled-up'. The coiled Kundalini is the female energy existing in latent form, not only in every human being but in every atom of the universe. It may frequently happen that an individual's Kundalini energy lies dormant through his or her entire lifetime and he or she is unaware of its existence. The object of the tantric practice of Kundalini-yoga is to awaken this cosmic energy and cause it to unite with Shiva, the Pure Consciousness pervading the whole universe.
In the concept of the Yoga Kundalini Upanishad:
"The divine power,
Kundalini shines
Like the stem of a young lotus;
Like a snake, coiled round upon herself,
She holds her tail in her mouth
And lies resting half asleep
At the base of the body."
The static, unmanifested Kundalini is symbolized by a serpent coiled into three and a half circles, with its tail in its mouth.
In the microcosm of the human body, the Goddess Kundalini appears as a dormant energy, but able, when she wakes up, to destroy the illusion of life and lead to liberation. She can be awakened through the practice of what is known as Kundalini-Yoga, a unique branch of esoteric Tantra.
When the Kundalini is ready to unfold, she ascends from the Muladhara Chakra to unite above the head with Shiva at the Sahasra Chakra. But before this merger she must ascend and pass through each of the five remaining chakras. As Kundalini reaches each chakra, that lotus opens and lifts its flower; and as soon as she leaves for a higher chakra, the lotus closes its petals and hangs down, symbolizing the activation of the energies of the chakra and their assimilation in Kundalini. The increasing number of lotus petals, in ascending order, may be taken to indicate the rising energy of the respective chakras, each functioning as a 'transformer' of energies from one potency to another.
In tantric art, an image created must correspond to the original canonical text; any omission, error or oversight is attributed to imperfect absorption or considered a sign of slackening of attention. In such an event, the image is discarded and the process of composing is deferred.
The process of image-making is an yoga discipline in itself. It is also believed to lead to spiritual deliverance. This belief shifts the objective of art from being an end in itself to being the means of an end. The intention of the artist is to express fundamental truths which are constant for all, and not just his own 'personal' truth. His path thus is one of selfless action, where there is a total annihilation of the ego. In such an art, it comes as no surprise therefore, that the artist has always remained anonymous.
The creative impulse of the artist is not stifled. The artist while undertaking creative activity intuitively realizes that his own self-expression is part of a universal and collective expression as a whole. This underlying unity acts as an awesome catalyst, convincing him of the sacred nature of his activity, and prompts him to adopt universal symbols in his creations. The Shiva-linga for example, is a balancing of the masculine and feminine ways of the world.
This archetypal symbol has been in existence even before the idea of history itself. The enduring popularity of its essential iconography is a pointer to its acceptance in the universal psychology.
Because of the vital nature of the task, ancient texts dwell at length on the qualities an artist must possess before he can embark on this spiritual journey. A tantric text for example, enumerates the following six essentials that a stone-carver must master:
The making of an iconographic image in Tantra art is considered the equivalent of the highest form of worship. This activity is seen as capable of opening up spiritual avenues for those who seek them. Accordingly the canonical texts set the highest standards for those who wish to traverse this path.
Conclusion
The art which has evolved out of tantra reveals an abundant variety of forms, varied inflections of tone and colors, graphic patterns, powerful symbols with personal and universal significance. It is especially intended to convey a knowledge evoking a higher level of perception, and tapping dormant sources of our awareness. This form of expression is not pursued like detached speculation to achieve mere aesthetic delight, but has a deeper meaning. Apart from aesthetic value, its real significance lies in its content, the meaning it conveys, and the philosophy of life it unravels. In this sense tantra art is visual metaphysics.