It is now well known that the body is constantly surrounded by an envelope of colours called "aura", which is an effect of lesya. Change in lesya will bring about a corresponding change in the colour of aura. That is why aura is predominated at different times by different colours such as black, red, yellow, blue of white.
Aura is not only influenced by the internal colour indices, but is also influenced by the colour of the external environment That is why the cause and effect relation between lesya and colours is reciprocal In other words, just as any change in lesyd would result in the change in the colour of aura, the change in the aura by the influence of the colours of the external environment would bring about a change in the lesya. This principle has been utilized in the "perception of the psychic colours" (lesya-dhyana) to transform the malevolent lesya into benevolent ones.