All that is "not-light" is, what the Is̱ẖrāqī thinkers call, "Absolute quantity", or "Absolute matter". It is only another aspect of the affirmation of light, and not an independent principle, as the followers of Aristotle erroneously hold. The experimental fact of the transformation of the primary elements into one another, points to this fundamental Absolute matter which, with its various degrees of grossness, constitutes the various spheres of material being. The absolute ground of all things, then, is divided into two kinds:-- (1). That which is beyond space--the obscure substance or atoms (essences of the As̱ẖ‘arite). (2). That which is necessarily in space--forms of darkness, e.g. weight, smell, taste, etc. The combination of these two particularises the Absolute matter. A material body is forms of darkness plus obscure substance, made visible or illuminated by the Abstract light. But what is the cause of the various forms of darkness? These, like the forms of light, owe their existence to the Abstract light, the different illuminations of which cause diversity in the spheres of being. The forms which make bodies differ from one another, do not exist in the nature of the Absolute matter. The Absolute quantity and the Absolute matter being identical, if these forms do exist in the essence of the Absolute matter, all bodies would be identical in regard to the forms of darkness. This, however, is contradicted by daily experience. The cause of the forms of darkness, therefore, is not the Absolute matter. And as the difference of forms cannot be assigned to any other cause, it follows that they are due to the various illuminations of the Abstract light. Forms of light and darkness both owe their existence to the Abstract Light. The third element of a material body--the obscure atom or essence--is nothing but a necessary aspect of the affirmation of light. The body as a whole, therefore, is completely dependent on the Primal Light. The whole Universe is really a continuous series of circles of existence, all depending on the original Light. Those nearer to the source receive more illumination than those more distant. All varieties of existence in each circle, and the circles themselves, are illuminated through an infinite number of medium-illuminations, which preserve some forms of existence by the help of "conscious light" (as in the case of man, animal and plant), and some without it (as in the case of minerals and primary elements). The immense panorama of diversity which we call the Universe, is, therefore, a vast shadow of the infinite variety in intensity of direct or indirect illuminations and rays of the Primary Light. Things are, so to speak, fed by their respective illuminations to which they constantly move, with a lover's passion, in order to drink more and more of the original fountain of Light. The world is an eternal drama of love. The different planes of being are as follow:--