What matters is not to apply a definition but to observe the characteristic signs of a disposition allotted by destiny or achieved by effort.  Among such symptoms are the tendency to sympathize with the sufferings of others, not in a sense of pity, but by opening the heart so that its radiation, without selection or discrimination, acts by itself as a balm of impersonal healing.  Other signs are material and spiritual generosity, as opposed to avarice and envy; the feeling of awareness of solidarity; an effective sense of responsibility; and the acceptance of all that makes for simplicity of thought and feeling, looking at all times for the essential point and rejecting perfunctory opinions and fashionable prejudices.

The light that the sun casts on the planets is the same for all, but each planet reflects it according to its own color, and the radiation that it returns is determined by its constitution.  In this inevitable diversity of color there is no treachery or false transmission, but it does explain why no teacher, however great, can all himself the sole possessor of the Truth.  He can only teach according to the type and “color” of his own soul, and to his capacity for faithful representation.  Beyond this limit he would be exceeding or misdirecting his mission, and adding a heavy responsibility to his burden of karma.