In Plato’s Phaedo, Socrates reflects the events from his life and reveals the most important ideas about the immortality of soul. In particular, the philosopher introduces the theory of separateness of immortal soul from the physical body by using a number of arguments.
In particular, Socrates refers to the analysis of oppositions, introduces recollection theory, and explains the concept of affinity to prove that soul is immortal and it is separate from the physical body.
From the perspective of the Opposites Arguments, if the physical body is mortal and physical, the soul is immortal and, therefore, it should not die. Because the body is subject to death in physical terms, the soul shapes its opposite.
To explain the existence of the opposites, Plato provides the analogy of cold and fire. Thus, in case the cold cannot be destructed and exists separately from fire, the latter can be destroyed by cold. Although the fire is destroyed, the cold will still exist. Similar opposites can be created while exemplifying the charges of magnets. Despite the fact that cold and fire are related to each other in terms of temperature differences.
They form the opposites and, nevertheless, they are linked to each other. At the same time, in case one object does not exist, the other object cannot exist. In this respect, can be said that fire can be identified as the absence of cold and, vice versa, cold personifies absence of fire. While identifying the analogy with body and soul, body cannot exist without soul and soul is the part of a body.
To prove the immortality of soul, it is necessary to refer to the theory of recollection. According to this theory, an individual possesses non-empirical knowledge, which implies that he/she can know something about the surrounding world at birth, but not in the course of living. In other words, people possess knowledge that is obtained as we gain experience about the object and event around use.
The theory, therefore, acknowledges the existence of previous knowledge about everything. The learning process is not associated with gaining knowledge from beyond, but recollecting what an individual is already aware of. The process of recollection is possible through proper questioning and, therefore, everything we know already can be regained.
While considering these assumptions, it is possible to assert that soul existed long before we have been born. What is more importantly, the theory also proves that the soul is immortal and it is capable of repeated reincarnation. Knowledge, therefore, forms the essence of soul eternity.
Each time the soul is incarnated in a new body, the knowledge could be forgotten because of the shock of birth. As a result, an individual perceives the recovery of knowledge as a learning process. The theory of recollection also justifies the existence of objective reality which does not depend on subjective evaluation because the matter of things existing in the world should not depend on the perception of individuals.
Finally, the evidence of existence of the soul can be analyzed from the viewpoint of affinity theory. According to this theory, the immortality is invisible and incorporeal whereas visible things are moral and corporeal. Within these perspectives, our soul is invisible and, therefore, it is immortal whereas our physical body can be seen and, therefore, it is mortal.
Although human bodies are subject to death, souls continue living. Unlike the two arguments discussed above, the affinity theory focuses on the nature of the soul. According to Plato, because the concept of soul is etymologically associated with the word “to breathe”, the philosophy demonstrates that, unlike breath, human soul cannot be blown away.
To shape the analogies under the affinity argument, soul is regarded as the form and it remains stable and unchanged, even when it encounters with the visible forms, such as physical body. When the body and soul are together, the latter controls the body because it is the nature of the soul to control the physical entity. In this respect, the soul can be identified with a divine being that is capable of ruling mortal beings.
Hence, the soul knows different forms owing to its ability to sense the material, although the soul is invisible. The affinity argument justifies the immortality of soul because it premises on the principles of analogies.
In other words, in case the soul knows forms and it is invisible, it can be imperishable. In contrast to the argument of analogy, the affinity concept can be presented as the argument about the nature of things. Therefore, the immortality of soul can be perceived as its function.
In conclusion, there proposed arguments, including opposites theory, theory of recollection, and affinity argument, the soul is immortal and it can exist separately of body.
With regard to the argument, the theory of opposites suits best for justifying the argument. In addition, the principle of analogues also contributes to understanding the concept of duality, which means that the body cannot exist without soul.