There are so many reasons by which we prove that Man's Soul is immortal and separable from his body. Some of the reasons that are given to prove the proposition by Persian Scholars Like FARÄBI and AVICENNA; SHAIKH ESHRÄGH, and other philosophers are as follows:ِ

      Aِ No one can forget his own very self, which is his soul; but every one does forget his body, and most of his organs. There are some organs in our body, that we may never know them in the whole life; but we know the self all the times, and we can never forget that we are, and we exist, in any condition! This fact proves that the Soul and the Body are two different and two separate entities.

      Bِ Our material body has some function that matter and material is not able to accomplish them. Our intellect, and understanding, for instance, are not the function of Matter. How can a stone or a piece of gold or any other material understand, think, and distinguish and finally decide!? Therefore it follows that the Soul is something other than the body.

      Cِ The body changes all the time. No one is like his childhood. The body changes all the time but the self never changes! Yes! You old man are that boy who....

      There are millions of billions of cells in our body. The red blood cells number to some twenty-five trillions, and yet each one of us has been originated as a single cell, or what they call it a fertilized egg. It was from this single egg that all our cells were then derived by a process of cleavage, or division!

      Cells are continually dying and being replaced in our body. Millions of dead cells are washed from the surface of the skin, every time we bathe. It has been scientifically estimated that during every second of our life ten millions of our red cells die, and are replaced by the new ones!

      It follows therefore, that our body is periodically dying a natural death, and is then revived! Thus far in your life, you have died a natural death so many times, and your old body has been perished, and replaced with a new one, and you have always been yourself without any change!

      Doesn't this change of our body prove that we are not the body, and that our body is only a veil upon us, or something like our clothes that are easily replaced?

      Dِ If all the organs of the body; like the heart, the head, the lungs, the limbs and etc., be replaced with that of another person, still the self and personality of the donor and acceptor will remain fixed and unchanged!

      Eِ A material body will never take a new form, unless the old form is destroyed. But the mind takes one form upon another up to millions of new forms, and retains the original forms as they are introduced to it.

      Millions of forms of knowledge, memories, poetries, and observances, are stored, and piled up, in your mind with their original forms all preserved; and you may remember and distinguish them whenever you want. This also proves that the mind and the material body are different substances.

      Fِ No material body can comprehend itself, but the self of Man does! A hand, for example, can never know its condition of being hot or cold, long or short, white or black; but, the soul does comprehend its existence; which is a proof that the soul is something other than the body.

      Gِ Too much work wears out every material instrument, and in particular the body organs, but will refresh the soul and renew its power for continuous working. Gaze at the sun for a while; and your eyes shall get temporarily blind, but the more you think, the more you will know, and the stronger your mental power shall become! This also can prove that our mind and body are two different substances.