The first of the Advaita Vedanta tattvas or principles is Shiva tattva, corresponding to the highest Brahman, or truth. In the next phase differentiation commences owing to the movement of Shakti tattva, the active or female principle. Shiva in this phase is thought of as being composed of mantras. Shakti is sometimes regarded as a separate tattva but more generally as inseparably united with Shiva.
The psychical tattvas are part of Maya tattva, and are not so much illusion as the level in which Karma is a natural part or the protoplasm from which all things grow. Between Maya and Purusha come five more tattvas, called envelopes. Their effect is to enclose and limit, thus turning the divine spirit into a human soul. The tattvas which are part of Maya are:
The physical tattvas are in the duality where one is Purusha (Powerful Intention), the soul or self, which is neither produced nor productive, and the other tattvas are all modifications of Prakṛiti (Pure Love) or matter, which is unproduced but productive. Prakṛiti means the original ground form of external existence. It is uncreated and indestructible, but it has a tendency to variation or evolution. Substance can only be produced from substance and properly speaking there is no such thing as origination but only manifestation. Causality is regarded solely from the point of view of material causes, that is to say the cause of a pot is clay and not the action of the potter. Thus the effect or product is nothing else than the cause in another shape: production is only manifestation and destruction is the resolution of a product into its cause. The Sâṅkhya affirms that there is nothing but successive manifestations of real existence. If clay is made into a pot and the pot is then broken and ground into clay again, the essential fact is not that a pot has come into existence and disappeared but that the clay continuously existing has undergone certain changes.
The tendency to evolution inherent in matter is due to the three guṇas. They are sattva, explained as goodness and happiness; rajas, as passion and movement; and tamas, as darkness, heaviness and ignorance. The word Guṇa is not easy to translate, for it seems to mean more than quality or mode and to signify the constituents of matter. When the three guṇas are in equilibrium then matter—Prakṛiti—is quiescent, undifferentiated and unmanifested. But as soon as the equilibrium is disturbed and one of the guṇas becomes preponderant, then the process of differentiation and manifestation begins.
The unmodified Prakṛiti stands first on the list of twenty-five principles. When emergence begins it produces first Buddhi or intellect, secondly Ahaṃkâra, which is perhaps best rendered by individuality, and next the five Tanmâtras or subtle elements. Buddhi, though meaning intellect, is used rather in the sense of ascertaining or perception. It is the faculty by which we distinguish objects and perceive what they are. It differs also from our conception of intellect in being, like Ahaṃkâra and all the subsequent developments of Prakṛiti, material, and must not be confused with the immaterial Purusha or soul. It is in fact the organ of thought, not in the sense of the brain or anything tangible, but a subtle substratum of all mental processes. But in what sense is it possible to say that this Buddhi exists apart from individuals, who have not come into being at this stage of cosmic evolution? This difficulty is not met by talking, as some commentators do, of cosmic as well as individual Buddhi, for even if all Prakṛiti is illuminated by Buddhi at this stage it is difficult to see what result can occur. To make the process of development coherent we must think of it not as a series of chronologically successive stages but rather as a logically connected series and an analysis of completely evolved beings, just as we might say that bones are covered with flesh and flesh with skin, without affirming that the bones have a separate and prior existence. Ahaṃkâra, which is, like Buddhi, strictly speaking a physical organ, means Ego-maker and denotes the sense of personality and individuality, almost the will. In the language of Indian philosophy it is the delusion or misconception which makes the soul imagine itself a personal agent and think, I see, I hear, I slay, I am slain, whereas the soul is really incapable of action and the acts are those of Prakṛiti.
The five subtle elements are the essences of sound, touch, sight, taste and smell conceived as physical principles, imperceptible to ordinary beings, though gods and Yogis can perceive them. They are named Tanmâtra, which signifies that only, indicating that they are concerned exclusively with one sense. Thus whereas the gross elements, such as earth, appeal to more than one sense and can be seen, felt and smelt, the subtle element of sound is restricted to the sense of hearing. It exists in all things audible but has nothing to do with their tangibility or visibility. There remain sixteen further modifications to make up the full list of twenty-four. They are the five organs of sense, the five organs of action, Manas or mind, regarded as a sixth and central sense, and also as the seat of will, and the five gross elements—earth, water, light, air and ether.