Yin-Yang is a symbol for the projection of the principle into the plane of existence in the form of apparently opposing but essentially complementary tendencies. Yin-Yang signifies unity within diversity. It is a universal archetype for the infinite aspect of the principle in which all manifestations are prefigured. The Absolute being infinite already contains within it all manifestations in the form of potentialities: Diversity is already prefigured in the Absolute by necessity of its infinitude.
The inverse archetype of this symbol pertains to the plane of existence in which the principle is projected in all manifestations: The relative being finite projects the unity and unicity of the principle in the form of actualities.
Diversity is prefigured in unity and unity is projected in diversity. The manifestation is prefigured in the principle, and the principle is projected in the manifestation. Yin-Yang signifies the archetype of such prefiguration and projection. It either reflects the essence of the Absolute or that of the relative.
The cross, however, is a different archetype which signifies the relation between the two realms: The vertical line signifies the descend of the Absolute principle in the form of revelation; the horizontal line signifies the reverberation of the revelation within the plane of existence. Much like when a stone falls into a pond making concentric outgoing waves, the principle vertically descends and horizontally propagates in the form of tradition. Religious traditions are horizontal reverberations of vertical revelations.
The cross also signifies the place of man in relation to both the principle and its manifestation. Man to be understood as the image of the absolute within the plane of the relative, the representative of the principle within manifestation, is the intersecting point of the vertical and horizontal lines of the cross. The vertical line which signified the descend in revelation above now signifies the ascend in salvation. Man is directly connected to the absolute principle, the connection being esoteric and inward. But man is also indirectly connected to the absolute principle through the manifestations of the principle; this is signified by the horizontal line of the cross. Manifestation being the projection of the principle, man’s relation to other human beings and the whole of existence is an indirect mode of connection to the absolute principle, the connection here being exoteric and outward. Prayer is man’s inward and direct connection to the principle, and service is man’s outward and indirect connection to the principle. Action is outward prayer while prayer is inward action, the action being constantly directed to the principle and with the consideration of the Unicity of the Real.
Thus, the cross is both the universal archetype for the relation between the principle and manifestation in general, and the universal archetype for the relation between man and the principle in particular.
World is nothing but a symbol. The fall of the fallen man, the condition of modern human, lies in his forgetfulness of the symbolic character of the world and himself in it. Existentialism perfectly signifies the modern predicament, not because existentialism offers a good description of this predicament but because it is itself symptomatic of this very predicament. Modern angst rose because man invested in the world as fact and essence and not as symbol and attribute.