Each soul may be pictured as being represented by an ovoid form, which at first is a mere colourless film, but which later, as the ego develops, begins to show a shimmering iridescence like a soap-bubble. Those who are connected with a physical body i.e., still in the physical body but may be able to travel to the causal plane in altered states like in meditation, are distinguishable from those in the disembodied state by a difference in the types of vibrations set up on the surface of their causal bodies.
It is therefore easy on this plane to see at a glance whether an individual is or is not in incarnation at the time. The immense majority, whether in or out of the body, are but dreamily semi-conscious, though few are now in the condition of mere colourless films. Those who are fully awake are marked and brilliant exceptions, standing out amid the less radiant crowds like stars of the first magnitude. Between these and the least-developed are ranged every variety of size and beauty, each thus representing the exact stage of evolution at which one has arrived.
The majority are not yet sufficiently developed to understand the purpose of the laws of the evolution in which they are engaged. They seek incarnation in obedience to the impulse of the Cosmic Will and also the blind thirst for manifested life. In their earlier stages, such entities cannot feel the intensely rapid and piercing vibrations of the highly refined matter of their own plane (the causal plane,). The strong and coarse but comparatively slow movements of the heavier matter of the physical plane are the only ones that can evoke any response from them.
Hence it is only on the physical plane that they feel themselves to be alive at all and this explains their strong craving for re-birth into earth-life. Thus for a certain period of time, their desire matches exactly with the law of evolution. Slowly their power of response increases and is awakened first to the higher and finer physical vibrations and still more slowly to those of the astral plane. Next, their consciousness begins to be centred on the astral plane i.e., consciousness begins to be centred in their emotions than in mere physical sensation.
At a later stage but always by the same process of learning one learns to centre one’s consciousness on the mental plane, to live according to the mental images which one has formed for oneself and so to govern one’s emotions by the mind. Yet further along the long road of evolution, the centre moves up to the causal body and the ego realises its true life. When that stage is reached, one will be found upon a higher sub-plane than the third, and the lower earthly existence will be no longer necessary.
As previously explained, the most advanced egos of this sub-plane develop to a point at which they are engaged in studying their past and learning a lot from retrospection, so that the impulses sent downwards become clearer and more definite, and translate themselves, in the lower consciousness, as imperative intuitions. On this third sub-plane are also to be found the causal bodies of the comparatively few members of the animal kingdom who are individualised.
Strictly speaking, these are not animals any longer. They are practically the only examples now to be seen of the quite primitive causal body, undeveloped in size, and coloured only very faintly by the first vibrations of newly born qualities. When the individualized animal retires into its causal body, to await its turn of evolution which will give it the opportunity of a primitive human incarnation, it seems to spend the time in a sort of delightful trance of the deepest peace and contentment.
(The article has been taken from the book ‘Life Beyond Death’ by Anil Sharma)