[Sidenote: II. In sciences.] 1. The Om of orthographers consisting of the four stages of speech; namely, ध्वनि पश्यन्ती मध्यमा and बैस्वरी । 2. Of Grammarians; the four parts of speech, nouns, verbs, prepositions and particles. 3. Of Ritualists; The hymns, liturgical precepts, Bráhmanas and ordinary language. 4. Of philologers or Sábdikas; the speech of serpents, beasts, birds and vernaculars. 5. Of Etymologists; The Rik, Yajur and Sáma Vedas and current language. 6. Of Spiritualists; The language of beasts, wild animals, musical instruments and soul. 7. Of Manu (IV. 126). The Pranava and the three Vyahrtis. (ॐ भूर्भ्रुवः स्वर्). 8. Of Manu (IV. 124). The Rik sacred to the gods, the Yajur relating to mankind and the Sáma concerning the manes, and its sound. 9. Of _Smártas_; The four stages;—of students, householders, mendicants and ascetics. 10. Of Puránas. The four Ages;—_Satya_, _Tretá_, _Dwápara_ and _Kali_. The four castes &c. [Sidenote: III. In Divinity] _A_ for _ápta_ or _Vyápta_—pervading all worlds, represents the divine hypostasis of Viswa. [Sidenote: 1. The 4 Conditions of Brahma.] _U_—for _Utkarshat_, _i. e._, more elevated than _A_; as the _Taijas_ than _Visva_. (तैजस). M—for _mána_ or measure, as the _prajná_ like a _prastha_ measures the above two. (प्रज्ञा). _Om_—_i. e._, the entire and without parts, is the fourth and perfect condition of Brahma. (ब्रह्म). [Sidenote: 2. The 4 states of the Soul.] _Á_ for the waking (Jágrat) state, when the soul is subject to gross senses. _U_—for the _swapna_ or dreaming state, when the soul is withdrawn from visible objects. M—the _susupta_ or sound sleeping state, in which the soul is unconscious of itself. _Om_—the absolute and perfect state of the soul viewing all in itself. [Sidenote: 3. The 4 Manifestations of God.] A—is external manifestation of the Universal soul in objects. _U_—Internal manifestation perceived in the operations of the soul in dream. M—unmanifested existence; or the self consciousness of the soul. Om—Unmanifest state of the soul, unmodified and inactive state. [Sidenote: 4. The 4 Titles of the soul.] A—_Viswa_ or _Vaiswánara_ who abides manifest in the waking state. U—_Taijasa_; abiding in dreams and knowing all without objects. M—_Prajná_, the perfect wise abiding in deep sleep. _Om_—Absolute Brahma called _Turíya_ which is perfect and all knowing. [Sidenote: The Four fold Tetrads:] I. A—_Áptah_, pervading. U—_Utkarsha_, Exalted. M—_Mána_, Measure. Om—_Brahma_, Absolute. II. _Jágrat_, Waking. _Swapna_, Dreaming. _Susupti_, Sleeping. _Sthira_, Calm. III.