so tenacious and subtle is this union that it can only be maintained by the shortest and straightest line between the eyes, and the smallest deviation from it, the slightest glance aside, completely destroys the unique character of this union. no objective trace of this relationship is left behind, as is universally found, directly or indirectly, in all other types of associations between men as, for example, in the interchange of words. the interaction of eye and eye dies in the moment in which the directness of the function is lost.

by the glance which reveals the other, one discloses himself. by the same act in which the observer seeks to know the observed, he surrenders himself to be understood by the observer. the eye cannot take unless at the same time it gives. the eye of a person discloses his own soul when he seeks to uncover that of another.

what occurs in this direct mutual glance represents the most perfect reciprocity in the entire field of human relations.

- george simmel on the mutual glance