As soon as we become conscious of existence we are at once confronted by the principle of duality, in that which is within us and that which is without, or the Me and the Not-me. The infant must gradually learn the idea of separateness, learn to distinguish that which is part of himself from that world beyond him, that his eager clutches cannot grasp. In fact at every moment of his life he is confronted with those "pairs of opposites" of which the Eastern philosophy tells us that the universe is composed. The Pythagoreans are said to have hated the duad, or the binary as it was also called, because it was to them the origin of differentiation and therefore of contrasts, discord, and the beginning of evil. It was that imperfect state into which the first manifested being fell when first detached from the Source of all Being. It was the point from which the two roads of Good and Evil bifurcated, and all that was double-faced or false the Pythagoreans called "binary," because to them One was alone Good, and Harmony, because from one alone no discord can proceed. And as the Monad was one and an odd number, the ancients called the odd numbers the only perfect ones, and considered them all as masculine and perfect, while even numbers were regarded as imperfect and were given only to the terrestrial and infernal deities. So that Virgil in his eighth eclogue asserts: "Unequal numbers please the Gods." (S. D. II. 602.)
But if we put aside these conceptions of the Greek and Latin races and go back in thought to the origin of all things, we cannot get away from the conviction that with the commencement of manifestation duality must begin. The moment we try to imagine the dawn of the universe we formulate the conception of life, and life is inconceivable without motion, which is change, either of place or condition, — is the action of attraction and repulsion, of the out-breathing and the in-breathing of the "Great Breath." Evil is the shadow of Good as Darkness is the shadow of Light, and everywhere throughout creation the opposite poles of positive and negative maintain the balances of universal law, and regulate the order of the heavenly bodies, or round a dew-drop on a blade of grass.
But as time went on and the earlier spiritual teachings came to be overlaid with grosser and more material ideas, the two equal and coordinate aspects of the Divine, that we call ordinarily Spirit and Matter, began to be considered as Good and Evil, and represented not complementary but antagonistic forces. Instead of the beautiful symbol of the Greek Caduceus bringing to men's minds the thought of the twin serpents of evolution encircling the Tree of Life, it had for them only the significance of everlasting struggle, of never-ending discord.
And this antagonism of forces that alone can set the universe in motion and preserve it in life, took the form in ancient Persia of the opposition of Deity and Devil, who were originally one in nature as in name. The exaltation of Ormuzd, the Spirit of Good, says Mr. Cox, in his Aryan Mythology, "carried the greatness of Ahriman (the Spirit of Evil) to a pitch which made him the creator and the sovereign of an evil universe at war with the Kosmos of the Spirit of Light. ... It was a dualism which divided the world between two opposing self-existent deities, while it professedly left to men the power of choosing whom they should obey."
With this Persian dualism the Jews came into contact during their captivity in Babylon, and the author of evil, the tempter, soon began to appear in strong opposition to the beneficent Father and God.
But Mr. Cox points out that while the Jewish mind readily absorbed this idea of the conflicting hierarchies, the one heavenly, the other diabolical, it nevertheless drew no sharp distinction between spirit and matter and had little definite idea of either the fact or the conditions of a life after death. It was left for Christianity to couple a distinct assurance of personal immortality with a profound belief in the devil and all his angels. Upon this rock did the early Christian fathers build their Church, for if we eliminate from their system of faith, the element of diabolical power, the whole fabric falls to pieces.
But when we go back to the original teachings of the Zend Avesta, that even as early as the days of the Babylonian captivity had become so corrupted, we find the principles of Good and Evil but the spiritual equivalents of Light and Darkness, Pain and Happiness; and as these were supposed to be exactly balanced against each other, so are their spiritual correlations. "Those old Spirits who are twins," says the Zend Avesta, "made known what is good and what evil in thoughts, words and deeds. Those who are good distinguish between the two; not so those who are evildoers."
If we turn to the pages of the Secret Doctrine we shall find all these ideas amplified and set forth with all that wealth of illustration for which that book is so remarkable, and on page 416 of vol. i, we seem to find the kernel of the whole thing in these words: "In human nature evil denotes only the polarity of matter and spirit, which principles are one per se, inasmuch as they are rooted in the Absolute. In Kosmos the equilibrium must be preserved. The operations of the two contraries produce harmony, like the centripetal and centrifugal forces which are necessary to each other, — mutually interdependent- — in order that both shall live. If one is arrested, the other will immediately become self-destructive."
But the principle of duality is not only shown in all the "pairs of opposites" that make up the universe, but also in the rhythmic changes of its periods of activity and repose. This Law of periodicity, of flux and reflux, of ebb and flow, is absolutely universal, and therefore governs not only the sweep of the stars through the heavens, the changes of the surface of the earth, the physical phenomena of health and disease, of animal and of human life, but is also the foundation of what we have learned to call the law of action and reaction in the thought of man. Every real student of literature and art, as well as of philosophy and religion, will recognise this principle as the cause of all the changes in painting and in poetry that have so diversified their character even within the last three or four hundred years. Take the Elizabethan era for instance, when our poetry reached its climax of perfection, for then physical life and physical luxury, the worship of beauty as it appeared to all the senses, had stimulated the emotional nature to its utmost and passionate strength and perfect music were the outcome of this stimulus. Then the ebb came, passionate strength degenerated into license and vice, the Puritan reaction towards virtue and the severest restraint began, and beauty became a term of reproach. The Restoration set the pendulum swinging towards license again, but feebly, for the abandonment to passion is not strength but weakness. Then came the artificial era of Pope and his fellows, when nature was tabooed and everything was done by rule. After the artificial came the natural back again, and the wave of reaction set in motion by Rousseau and the influences of the French Revolution gave us Wordsworth and the Lake School, with its range from the simplicity of grandeur and nobility to the simplicity of childishness. Another reaction, and the worship of beauty in form and color — especially color — began with the Pre-Raphaelite painters and poets, and Swinburne and Rosetti swept us away in a flood of bright tints and soft melody, while Tennyson expressed the triumph of artistic feeling and Browning the reaction against it. Now the influx of poetry that came into the world with the poets born mostly in the first quarter of our century, has died out: nearly all the great singers are dead; and the reaction gives us the triumph of form, dainty lyrics that pride themselves on the accurate observance of rule and on keeping the exact measure of the triolet, the ballade, the rondeau.
And we might go through the same sort of analysis in every department of thought, for everywhere through the universe the principle of "action and reaction" prevails. Old Geoffrey Ghaucer realised this great truth when he wrote some five hundred years ago, those wise words:
"Hearken this counsel for thy secureness:
Upon thy glad day ever have in mind
The unknown woe of harm that comes behind."
Not that we should always be looking forward to a possible misfortune, but that we should realize that there is nothing stable in this world where everything is most literally in a state of change and transition. "Let him that standeth take heed lest he fall," for it is on our "glad day," when everything looks bright to us, when our powers seem strongest, our position most secure, that we are nearest to "the unseen woe of harm that comes behind."
And of course the reverse of the picture is equally true, and the darkest hour of night precedes the hour of dawn. Dark hours must come to all of us, when our bodily strength fails and our mental powers are clouded, when all relation to the spiritual world above us seems cut off, and we drift like idle weeds upon a midnight sea. But even then the tide is turning, and if we only keep our hearts faithful to the right, the sun will shine for us again and the faint light of dawn broaden into the perfect day.