Others say that it consists of the brain with the addition...
Others say that it consists of the brain with the addition of a mysterious spark which leaves our bodies at the time of death. As you know, the philosophers have reflected a great deal on the spirit: its nature, its locus in the body, whether it is mortal or eternal, but none of these questions has yet been solved, despite the continuing of efforts of scholars.
“Recently many scholars have decided to study the matter from another point of view by putting the whole question of the spirit aside as too complex and obscure and studying instead the mind or the soul i.e., the totality of man's feelings, beliefs and thoughts.” ( Rushd va Zindagi, p.
Then We made the sperm into coagulated blood, the coagulated blood into a formless piece of flesh, and the flesh into bones, and finally We clothed the bones in flesh. Thus We brought forth a new creation. Glorified be the perfect power of the Best of creators!” (23:12-14). “Then God completed the creation of man and inhaled in him of His own spirit and appointed for you eyes, ears, and a heart. How little you men give thanks” (32:9) .
“When I complete the outer creation of man and breathe into him of My own spirit, prostrate yourselves before him, o angels!” (15:29) . These verses describe the successive stages of creation that succeed the coming into being of the drop of sperm, the final result of which is a perfected human body; they indicate that something more valuable and significant is at issue than the creation of a mere corporeal form.
They indicate that the infusion of the spirit into man's bodily form constitutes itself a “new creation,” which belongs to a category different from the various stages of the evolution of man's bodily form, each of which is necessarily accompanied by the traces and properties of matter. The spirit is a different essence, bearing no similarity to the things created before it.