According to Suhrawardi, there are fifteen categories of light, which are "the purpose of the path of knowledge". These visionary lights which emanate from the world of intellect are the essence of power and knowledge and he who experiences these lights also attains the power to rule over the material world. The necessary condition for this experience is, however, "separation" or "تجريد" from one's corporeal body. These lights are:
1- A light which shines upon the novice and is pleasant but not permanent.
2- A light which shines upon others and is more like a lighting bolt.
3- A light that is soothing and enters the heart of the Gnostics. It is as if warm water is poured upon you, a pleasant sensation is then experienced.
4- A light that descends upon the hearts of the men of vision and lasts a very long time. This is a dominant light which induces a form of intoxication.
5- A light of extreme grace and pleasure which is induced through the power of love.
6- A light that burns and is induced through knowledge that is attained through intellection or "تفكر".
7- A light which at first is luminous and is more intense that the light of sun.
8- A luminous and pleasant light appearing as if it is coming from the hair, and lasts a very long time.
9- An emanating light which is painful and yet pleasurable.
10- A light that is coming from some figures and lies in the brain.
11- A light that emanates from the self "نفس" and shines upon the entire spiritual components.
12- A light whose attainment is marked by intensity.
13- A light that gives birth to the self and appears to be suspended. The incorporeality of the self can be observed through this light.
14- A light which induces a special heaviness such as it exerts pressure beyond someone's ability.
15- A light that is the cause of the movement of the body and the material self.
Suhrawardi tells us that he has seen and experienced these lights and that they are the reasons how sages are able to perform miracles.