The criteria of unity in a living existent

Man like other animals is made-up of numerous cells. Each cell is in a continual state of transformation and deterioration. The number of cells in a human being since his birth is constantly fluctuating and, one will never find an individual whose composing elements of the body have remained the same and have not transformed or fluctuated.

If we focus upon these transformations and mutations, which occur in animals and within man, the question arises as to why do we refer to this ‘transforming assemblage’ as one existent, is it not possible that through its course of life it has in fact changed several times?

The simple answer that can be given to this question is that the criteria of unity which is in every living existent, is the timely correlation between the cells and not an inappropriate replacement of them. Every cell gradually dies and a new cell takes its place. This happens throughout the course of time and this new ‘transformed assemblage’ is still known as one or the same existent. However, this answer is not satisfying because; if we take the example of a building which has gradually had all its old bricks replaced by new bricks, whilst still maintaining the same outward form, it would not be called the same building. In particular those who are aware of the replacement would not consider the building to be the same as the old previous structure.

Nevertheless, it is possible for the answer given, to be modified in this way; the gradual replacement in a living existent is due to the natural factors within an organism as compared to that of a building, which is due to unnatural and outward factors. Hence, the true and internal replacement of cells cannot be related to that of bricks. This answer is based upon the acceptance of a unity in the natural elements and factors that transforms the cells while maintaining the unity of an organism.

Therefore the question will be directed in regard to the criteria of unity in the natural element or factor itself and the reality of this natural element.

According to a famous philosophical view, the criteria of unity being in every natural or living existent is an abstract decree (which is the equivalent to it being not compound) and imperceptive by the name of ‘nature’ or (genus) ‘form’ and does not change due to the transformation or replacement of matter. The natural factor in these living existents, which is comprised of different actions such as growth, digestion, reproduction, etc is called the soul (nafs).

Previous philosophers have regarded the mineral and animal soul as materialistic and the human soul as immaterial. Many of the Islamic philosophers such as Sadruddin Shirazi regarded the animal soul as having different levels of immateriality and recognized perceptiveness, and will (irādah) as the signs of immaterial existents.

However the previous and present materialistic philosophers (positivist) have limited the existent to matter and denied the immateriality of the spirit and the latter have completely denied the basis of anything imperceptible. The positivists do not accept the ‘form’ (genus) or nature of any existent as it is immaterial and will not produce a correct answer for representing the criteria of unity in the living existent.

On the basis that it is the unity in minerals, which is the soul of the mineral, the mineral kingdom is categorized by a special form or soul, which is substantially susceptible and when this potentiality or susceptibility is destroyed, the soul and the form of it is also destroyed. But, if the same substance accepts life or a new form, then a new mineral soul is allotted to it and a new plant after the old one has been destroyed (even if perfect in resemblance) will not be considered as the same old plant.

However for the animal and human soul, the soul is immaterial and can remain even after the body has been completely destroyed. Likewise, the new replaced or transformed cells preserve the unity in a person, and s/he is known as that very previous and same individual. Even before death the unity of the spirit in a particular body is the criteria of the unity.

Those who regard the existence (wujūd) of humans and animals as being limited to this material realm and their spirit as being imperceptible and as a component of their physical body and thus destroyed along with the material destruction of the body, will not grasp the correct understanding of Resurrection.

While concluding one must say that the only way one will form the correct understanding of life after death, is when one understands that the spirit is other than but essential to the material body. Therefore, the existence of the spirit must be accepted and it must be regarded as an essential substance of the body and not an accidental occurrence of the body. Thirdly it must be understood that the spirit is independent and eternal even after the destruction of the body, unlike those transformed material matters which become destroyed after the outward and bodily destruction.

The role of the spirit in the existence of man

Another noteworthy point that needs to be remembered is that the composition of man i.e. of spirit and body, is not similar to that of the compositions found in chemistry. In chemistry two or more elements are proportioned to form a compound element, such as the composition of oxygen and hydrogen, which if separated from each other, the existent of water as an element is destroyed.

The spirit is an essential substance of the human being. It forms and preserves the humanity and personality of man, and it is due to this very reason that the transformation and replacement of cells cannot destroy the unity of man. Hence the true criterion of unity in man is the very spirit of man.

The Noble Qur’an while indicating the reality of the spirit answers those who deny the truth of Resurrection and says:

“Say, ‘You will be taken away by the angel of death, who has been charged with you. Then you will be brought back to your Lord.’” (al-Sajdah:11) Hence the perpetuity of personality and humanness is due to that

entity which the angel of death seizes, and not due to the thing that becomes scattered or dispersed in the earth.


1- Is the timely transformation of cells in a unit considered as the criteria for unity? Why?

2- What is the criterion of unity in organisms?

3- Explain the famous philosophical viewpoint on the criteria of unity in living existents.

4- What are the differences between the natural ‘form’ and the soul?

5- What is the difference between the mineral soul and the animal soul? What is the effect of this difference upon the issue of Resurrection?

6- What does the correct understanding of Resurrection require?