To Zoroaster — the ancient sage of Iran — must always be assigned the first place in the intellectual history of Iranian Aryans who, wearied of constant roaming, settled down to an agricultural life at a time when the Vedic Hymns were still being composed in the plains of Central Asia. This new mode of life and the consequent stability of the institution of property among the settlers, made them hated by other Aryan tribes who had not yet shaken off their original nomadic habits, and occasionally plundered their more civilised kinsmen. Thus grew up the conflict between the two modes of life which found its earliest expression in the denunciation of the deities of each other — the Devas and the Ahuras. It was really the beginning of a long individualising process which gradually severed the Iranian branch from other Aryan tribes, and finally manifested itself in the religious system of Zoroaster — the great prophet of Iran who lived and taught in the age of Solon and Thales. In the dim light of modern oriental research we see ancient Iranians divided between two camps — partisans of the powers of good, and partisans of the powers of evil — when the great sage joins their furious contest, and with his moral enthusiasm stamps out once for all the worship of demons as well as the intolerable ritual of the Magian priesthood.
It is, however, beside our purpose to trace the origin and growth of Zoroaster's religious system. Our object, in so far as the present investigation is concerned, is to glance at the metaphysical side of his revelation. We, there‑fore, wish to fix our attention on the sacred trinity of philosophy — God, Man and Nature.
Geiger, in his "Civilisation of Eastern Iranians in Ancient Times", points out that Zoroaster inherited two fundamental principles from his Aryan ancestry. — (I) There is law in Nature. (2) There is conflict in Nature. It is the observation of law and conflict in the vast panorama of being that constitutes the philosophical foundation of his system. The problem before him was to reconcile the existence of evil with the eternal goodness of God. His predecessors worshipped a plurality of good spirits all of which he reduced to a unity and called it Ahuramazda. On the other hand he reduced all the powers of evil to a similar unity and called it Druj-Ahriman. Thus by a process of unification he arrived at two fundamental principles which, as Haug shows, he looked upon not as two independent activities, but as two parts or rather aspects of the same Primary Being. Dr. Haug, therefore, holds that the Prophet of ancient Iran was theologically a monotheist and philosophically a dualist. But to maintain that there are “twin” spirits — creators of reality and nonreality — and at the same time to hold that these two spirits are united in the Supreme Being, is virtually to say that the principle of evil constitutes a part of the very essence of God; and the conflict between good and evil is nothing more than the struggle of God against Himself. There is, therefore, an inherent weakness in his attempt to reconcile theological monotheism with philosophical dualism, and the result was a schism among the prophet's followers. The Zendiks whom Dr. Haug calls heretics, but Who were, I believe, decidedly more consistent than their opponents, maintained the independence of the two original spirits from each other, while the Magi upheld their unity. The upholders of unity endeavoured, in various ways, to meet the Zendiks; but the very fact that they tried different phrases and expressions to express the unity of the "Primal Twins", indicates dissatisfaction with their own philosophical explanations, and the strength of their opponent's position. Shahrastānī describes briefly the different explanations of the Magi. The Zarwānians look upon Light and Darkness as the sons of Infinite Time. The Kiyūmarthiyya hold that the original principle was Light which was afraid of a hostile power, and it was this thought of an adversary mixed with fear that led to the birth of Darkness. Another branch of Zarwānians maintain that the original principle doubted concerning some-thing and this doubt produced Ahriman. Ibn ῌazm speaks of another sect who explained the principle of Darkness as the obscuration of a part of the fundamental principle of Light itself.
Whether the philosophical dualism of Zoroaster can be reconciled with his monotheism or not, it is unquestionable that, from a meta-physical standpoint, he has made a profound suggestion in regard to the ultimate nature of reality. The idea seems to have influenced ancient Greek Philosophy as well as early Christian Gnostic speculation, and through the latter, some aspects of modern western thought.
As a thinker he is worthy of great respect not only because he approached the problem of objective multiplicity in a philosophical spirit; but also because he endeavoured, having been led to metaphysical dualism, to reduce his Primary Duality to a higher unity. He seems to have perceived, what the mystic shoemaker of Germany perceived long after him, that the diversity of nature could not be explained without postulating a principle of negativity or self-differentiation in the very nature of God. His immediate successors did not, however, quite realise the deep significance of their master's suggestions; but we shall see, as we advance, how Zoroaster's idea finds a more spiritualised expression in some of the aspects of later Persian thought.
Turning now to his Cosmology, his dualism leads him to bifurcate, as it were, the whole universe into two departments of being — reality i.e. the sum of all good creations flowing from the creative activity of the beneficial spirit, and non-reality i.e. the sum of all evil creations proceeding from the hostile spirit. The original conflict of the two spirits is manifested in the opposing forces of nature, which, there-fore, presents a continual struggle between the powers of Good and the powers of Evil. But it should be remembered that nothing intervenes between the original spirits and their respective creations. Things are good and bad because they proceed from good or bad creative agencies, in their own nature they are quite indifferent. Zoroaster's conception of creation is fundamentally different from that of Plato and Schopenhauer to whom spheres of empirical reality reflect non-temporal or temporal ideas which, so to speak, mediate between Reality and Appearance. There are, according to Zoroaster, only two categories of existence, and the history of the universe is nothing more than a progressive conflict between the forces falling respectively under these categories. We are, like other things, partakers of this struggle, and it is our duty to range ourselves on the side of Light which will eventually prevail and completely vanquish the spirit of Darkness. The metaphysics of the Iranian Prophet, like that of Plato, passes on into Ethics, and it is in the peculiarity of the Ethical aspect of his thought that the influence of his social evironments is most apparent.
Zoroaster's view of the destiny of the soul is very simple. The soul, according to him, is a creation, not a part of God as the votaries of Mithra afterwards maintained. It had a beginning in time, but can attain to everlasting life by fighting against Evil in the earthly scene of its activity. It is free to choose between the only two courses of action —good and evil; and besides the power of choice the spirit of Light has endowed it with the following faculties: —
2. Vital force.
- The Soul — The Mind.
- The Spirit — Reason.
- The Farāwashi — A kind of tutelary spirit which acts as a protection of man in his voyage towards God.
The last three faculties are united together after death, and form an indissoluble whole. The virtuous soul, leaving its home of flesh, is borne up into higher regions, and has to .pass through the following planes of existence: —
1. The Place of good thoughts.
- The Place of good words.
- The Place of good works.
- The Place of Eternal Glory — Where the individual soul unites with the principle of Light without losing its personality.
Mānī and Mazdak
We have seen Zoroaster's solution of the problem of diversity, and the theological or rather philosophical controversy which split up the Zoroastrian Church. The half-Persian Mānī — "the founder of Godless community" as Christians styled him afterwards — agrees with those Zoroastrians who held the Prophet's doctrine in its naked form, and approaches the question in a spirit thoroughly materialistic. Originally Persian his father emigrated from Hamadān to Babylonia where Mānī was born in 215 or 216 A.D. — the time when Buddhistic Missionaries were beginning to preach Nirvāna to the country of Zoroaster. The eclectic character of the religious system of Mānī, its bold extension of the Christian idea of redemption, and its logical consistency in holding, as a true ground for an ascetic life, that the world is essentially evil, made it a real power which influenced not only Eastern and Western Christian thought, but has also left some dim marks on the development of metaphysical speculation in Persia. Leaving the discussion of the sources of Mānī's religious system to the orientalist, we proceed to describe and finally to determine the philosophical value of his doctrine of the origin of the Phenomenal Universe.
The Paganising gnostic, as Erdmann calls him, teaches that the variety of things springs from the mixture of two eternal Principles — Light and Darkness — which are separate from and independent of each other. The Principle of Light connotes ten ideas — Gentleness, Knowledge, Understanding, Mystery, Insight, Love, Conviction, Faith, Benevolence and Wisdom. Similarly the Principle of Darkness connotes five eternal ideas — Mistiness, Heat, Fire, Venom, Darkness. Along with these two primordial principles and connected with each, Mānī recognises the eternity of space and earth, each connoting respectively the ideas of knowledge, understanding, mystery, insight, breath, air, water, light and fire. In darkness — the feminine Principle in Nature — were hidden the elements of evil which, in course of time, concentrated and resulted in the composition, so to speak, of the hideous looking Devil — the principle of activity. This first born child of the fiery womb of darkness, attacked the domain of the King of Light who, in order to ward off his malicious onslaught, created the Primal man. A serious conflict ensued between the two creatures, and resulted in the complete vanquishment of the Primal Man. The evil one, then, succeeded in mixing together the five elements of darkness with the five elements of light. Thereupon the ruler of the domain of light ordered some of his angels to construct the Universe out of these mixed elements with a view to free the atoms of light from their imprisonment. But the reason why darkness was the first to attack light, is that the latter, being in its essence good, could not proceed to start the process of admixture which was essentially harmful to itself. The attitude of Mānī's Cosmology, therefore, to the Christian doctrine of Redemption is similar to that of Hegelian Cosmology to the doctrine of the Trinity. To him redemption is a physical process, and all procreation, because it protracts the imprisonment of light, is contrary to the aim and object of the Universe. The imprisoned atoms of light are continually set free from darkness which is thrown down in the unfathomable ditch round the Universe. The liberated light, however, passes on to the sun and the moon whence it is carried by angels to the region of light — the eternal home of the King of Paradise — "Pîd i vazargîî" — Father of greatness.
This is a brief account of Mānī's fantastic Cosmology. He rejects the Zoroastrian hypo-thesis of creative agencies to explain the problem of objective existence. Taking a thoroughly materialistic view of the question, he ascribes the phenomenal universe to the mixture of two independent, eternal principles, one of which (darkness) is not only a part of the universe — stuff, but also the source wherein activity resides, as it were, slumbering, and starts up into being when the favourable moment arrives. The essential idea of his cosmology, therefore, has a curious resemblance with that of the great Hindu thinker Kapila, who accounts for the production of the universe by the hypothesis of three gunas, i. e. Sattwa (goodness), Tamas (darkness), and Rajas (motion or passion) which mix together to form Nature, when the equilibrium of the primordial matter (Prakritī) is upset. Of the various solutions of the problem of diversity which the Vedāntist solved by postulating the mysterious power of "Māyā", and Leibniz, long afterwards, explained by his doctrine of the Identity of Indiscernibles, Mānī's solution, though childish, must find a place in the historical development of philosophical ideas. Its philosophical value may be insignificant; but one thing is certain, i.e. Mānī was the first to venture the suggestion that the Universe is due to the activity of the Devil, and hence essentially evil — a proposition which seems to me to be the only logical justification of a system which preaches renunciation as the guiding principle of life. In our own times Schopenhauer has been led to the same conclusion; though, unlike Mānī, he supposes the principle of objectification or individuation — "the sinful bent" of the will to life — to exist in the very nature of the Primal Will and not independent of it.
Turning now to the remarkable socialist of ancient Persia — Mazdak. This early prophet of communism appeared during the reign of Anūshīrwān the Just (531—578 A. D.), and marked another dualistic reaction against the prevailing Zarwānian doctrine. Mazdak, like Māni, taught that the diversity of things springs from the mixture of two independent, eternal principles which he called Shīd (Light) and Tār (Darkness). But he differs from his predecessor in holding that the fact of their mixture as well as their final separation, are quite accidental, and not at all the result of choice. Mazdak's God is endowed with sensation, and has four principal energies in his eternal presence — power of discrimination, memory, understanding and bliss. These four energies have four personal manifestations who, assisted by four other persons, superintend the course of the Universe. Variety in things and men is due to the various combinations of the original principles.
But the most characteristic feature of the Mazdakite teaching is its communism, which is evidently an inference from the cosmopolitan spirit of Mānī's Philosophy. All men, said Mazdak, are equal; and the notion of individual property was introduced by the hostile demons whose object is to turn God's Universe into a scene of endless misery. It is chiefly this aspect of Mazdak's teaching that was most shocking to the Zoroastrian conscience, and finally brought about the destruction of his enormous following, even though the master was supposed to have miraculously made the sacred Fire talk, and bear witness to the truth of his mission.
We have seen some of the aspects of Pre-Islamic Persian thought; though, owing to our ignorance of the tendencies of Sāssānīde thought, and of the political, social, and intellectual conditions that determined its evolution, we have not been able fully to trace the continuity of ideas. Nations as well as individuals, in their intellectual history, begin with the objective. Although the moral fervour of Zoroaster gave a spiritual tone to his theory of the origin of things, yet the net result of this period of Persian speculation is nothing more than a materialistic dualism. The principle of Unity as a philosophical ground of all that exists, is but dimly perceived at this stage of intellectual evolution in Persia. The controversy among the followers of Zoroaster indicates that the movement towards a monistic conception of the Universe had begun; but we have unfortunately no evidence to make a positive statement concerning the pantheistic tendencies of Pre-Islamic Persian thought. We know that in the 6th century A. D., Diogenes, Simplicius and other Neo-Platonic thinkers, were driven by the persecution of Justinian, to take refuge in the court of the tolerant Anūshīrwān. This great monarch, moreover, had several works translated for him from Sanskrit and Greek, but we have no historical evidence to show how far these events actually influenced the course of Persian thought. Let us, therefore, pass on to the advent of Islām in Persia, which completely shattered the old order of things, and brought to the thinking mind the new concept of an uncompromising monotheism as well as the Greek dualism of God and matter, as distinguished from the purely Persian dualism of God and Devil.
Some European Scholars have held Zoroaster to be nothing more than a mythical personage. But since the publication of Professor Jackson's admirable Life of Zoroaster, the Iranian Prophet has, I believe, finally got out of the ordeal of modern criticism.
 "In the beginning there was a pair of twins, two spirits, each of a peculiar activity". Yas. XXX. 1
 The more beneficial of my spirits has produced, by speaking it, the whole rightful creation". Yas. XIX. 9.
 The following verse from Bundadish Chap. I. will indicate the Zendik view: — "And between them (the two principles) there was empty space, that is what they call "air" in which is now their meeting"
 Shahrastānī; ed. Cureton, London, 1846, pp. 182-185.
 Ibn ῌazm — Kitāb al-Milal w'al-Niḥal. Ed. Cairo. Vol. II, p. 34.
 In connection with the influence of Zoroastrian ideas on Ancient Greek thought, the following statement made by Erdmann is noteworthy, though Lawrence Mills (American Journal of Philology Vol. 22) regards such influence as improbable: — "The fact that the handmaids of this force, which he (Heraclitus) calls the seed of all that happens and the measure of all order, are entitled the "tongues" has probably been slightly ascribed to the influence of the Persian Magi. On the other hand he connects himself with his country's mythology, not indeed without a change of exegesis when he places Apollo and Dionysus beside Zeus, i.e. The ultimate fire, as the two aspects of his nature". History of Philosophy Vol. I, p. 50.
It is, perhaps, owing to this doubtful influence of Zoroastrianism on Heraclitus that Lassalle (quoted by Paul Janet in his History of the Problems of Philosophy Vol.II, p.147) looks upon Zoroaster as a precursor of Hegel.
Of Zoroastrian influence on Pythagoras Erdmann says: —
"The fact that the odd numbers are put above the even has been emphasised by Gladisch in his comparison of the Pythagorian with the Chinese doctrine, and the fact, moreover, that among the oppositions we find those of light and darkness, good and evil, has induced many, in ancient and modern times, to suppose that they were borrowed from Zoroastrianism." Vol. I, p. 33.
 Among modern English thinkers Mr. Bradley arrives at a conclusion similar to that of Zoroaster. Discussing the ethical significance of Bradley's Philosophy, Prof. Sorley says: — "Mr. Bradley, like Green, has faith in an eternal reality which might be called spiritual, inasmuch as it is not material; like Green he looks upon man's moral activity as an appearance -- what Green calls a reproduction — of this eternal reality. But under this general agreement there lies a world of difference. He refuses by the use of the term self-conscious, to liken his Absolute to the personality of man, and he brings out the consequence which in Green is more or less concealed, that the evil equally with the good in man and in the world are appearances of the Absolute". Recent tendencies in Ethics, pp. 100—101.
 This should not be confounded with Plato's non-being. To Zoroaster all forms of existence proceeding from the creative agency of the spirit of darkness are unreal; because, considering the final triumph of the spirit of Light, they have a temporary existence only
 Mithraism was a phase of Zoroastrianism which spread over the Roman world in the second century. The partisans of Mithra worshipped the sun whom they looked upon as the great advocate of Light. They held the human soul to be a part of God, and maintained that the observance of a mysterious cult could bring about the souls' union with God. Their doctrine of the soul, its ascent towards God by torturing the body and finally passing through the sphere of Aether and becoming pure fire, offers some resemblance with views entertained by some schools of Persian Ṣūfīism.
 Geiger's Civilisation of Eastern Iranians, Vol. I, p.124.
 Dr. Haug (Essays p. 206) compares these protecting spirits with the ideas of Plato. They, however, are not to be understood as models according to which things are fashioned. Plato's ideas, moreover, are eternal, non-temporal and non-spatial. The doctrine that everything created by the spirit of Light is protected by a subordinate spirit has only an outward resemblance with the view that every spirit is fashioned according to a perfect supersensible model.
 3 The Ṣūfī conception of the soul is also tripartite. According to them the soul is a combination of Mind, heart and spirit (Nafs, QaIb, Ruh). The "heart" is to them both material and immaterial or, more properly, neither — standing midway between soul and mind (Nafs and Rub), and acting as the organ of higher know-ledge. Perhaps Dr. Schenkel's use of the word "conscience" would approach the sufI idea of "heart"
 Geiger Vol. I, p. 104. (The stiff Cosmology has a similar doctrine concerning the different stages of existence through which the soul has to pass in its journey heavenward. They enumerate the following five Planes; but their definition of the character of each plane is slightly different: —
1. The world of body. (Nāsūt).
2. The world of pure intelligence. (Malakūt).
3. The world of power. (Jabrūt).
4. The world of negation. (Lāhūt).
5. The world of Absolute Silence. (Hāhūt).
The sufīs probably borrowed this idea from the Indian Yogīs who recognise the following seven Planes: — (Annie Besant: Reincarnation, p. 3o).
1. The Plane of Physical Body.
2. The Plane of Etherial double.
3. The Plane of Vitality.
4. The Plane of Emotional Nature.
5. The Plane of Thought.
6. The Plane of Spiritual soul — Reason.
7. The Plane of Pure Spirit.
 Sources used:—
(a) The text of Muhammad ibn Isḥāq, edited by Flügel, pp. 52—56.
(b) Al-Ya'qūbī: ed. Houtsma, 1883, Vol. I, pp. 180—181.
(c) Ibn ῌazm: Kitāb al-Milal w'al-Niḥal: ed. Cairo, Vol. II, p. 36.
(d) Shahrastānī: ed. Cureton, London, 1846, pp. 188—192.
(e) Encyclopaedia Britannica, Article on Mānī.
(f) Salemann: Bulletin de l'Academié des Sciences de St. Peters-burg Series IV, 15 April 1907, pp. 175—184. F. W. K. Muller: Handschriften — Reste in Estrangelo — Schrift aus Turfan, Chinesisch — Turkistan, Tell I, II; Sitzungen der Königlich Preussischen Akademie der Wissenschaften, 11 Feb. 1904, pp. 348—352; and Abhandlungen etc. 1904.
 Sources used: —
(a) Siyāsat Nāmah Nizām al-Mulk: ed. Charles Schefer, Paris, 1897, pp. 166—181.
(b) Shahrastānī: ed. Cureton, pp. 192—194.
(c) Al-Ya'qūbī: ed. Houtsma, 1883, Vol. I, p. 186.
(d) Al-Bīrūnī: Chronology of Ancient Nations: tr. E. Sachau, London, 1879, p. 192.
 "If I see aright, five different conceptions can be distinguished for the period about 400 A.D. First we have the Manichaean which insinuated its way in the darkness, but was widely extended even among the clergy". (Harnack's History of Christian Dogma, Vol. V, p. 56). "From the anti-Manichaean controversy sprang the desire to conceive all God's attributes as identical i. e. the interest in the indivisibility of God". (ibid. Vol. Y, p. 120).
 Some Eastern sources of information about Mānī's Philosophy (e. g. Ephraim Syrus mentioned by Prof. A. A. Bevan in his Introduction to the Hymn of the Soul) tell us that he was a disciple of Bardesanes, the Syrian gnostic. The learned author of "al-Fihrist", however, mentions some books which Mānī wrote against the followers of the Syrian gnostic. Burkitt, in his lectures on Early Eastern Christianity, gives a free translation of Bardesanes' De Fato, the spirit of which I understand, is fully Christian, and thoroughly opposed to the teaching of Mānī. Ibn ῌazm, however, in his Kitāb al-Milal w'al-Niḥal (Vol. II, p. 36) says, "Both agreed in other respects, except that Mānī believed darkness to be a living principle."
 It is interesting to compare Māni's Philosophy of Nature with the Chinese notion of Creation, according to which all that exists flows from the Union of Yin and Yang. But the Chinese reduced these two principles to a higher unity:— Tai Keih. To Mānī such a reduction was not possible; since he could not conceive that things of opposite nature could proceed from the same principle.
 Thomas Aquinas states and criticises Māni's contrariety of Primal agents in the following manner: —
(a) What all things seek even a principle of evil would seek.
But all things seek their own self-preservation.
- Even a principle of evil would seek its own self-preservation.
(b) What all things seek is good.
But self-preservation is what all things seek.
- Self-preservation is good.
- But a principle of evil would seek its own self-preservation. A principle of evil would seek some good — which shows that it is self-contradictory.
God and His Creatures, Book II, p. 105. Rickaby's Tr.
 The Zarwānian doctrine prevailed in Persia in the 5th century B. C. (See Z. D. M. G., Vol. LVII, p. 562).