The Greek philosopher Plato, born in Athens in 428/427 BC, came from a noble family. Some close relatives of his were members of the governing bodies of the oligarchic tyranny in Athens as well as of the subsequently re-established democracy. Plato himself decided against a political career. As Aristotle reports, Plato was first a follower of the teachings of the Heraclitean Kratylos. From young adulthood he became a student of Socrates. He strove to lead a virtuous and godly life in which justice and the realisation of the divine good were paramount.
The soul plays a central role in Plato's work. It is the soul that brings man closer to the divine, that is immortal and reincarnates until man is reconnected with his divine origin. In the Timaios, Plato's late work, we learn about the origin of creation, including the soul. First, the ever-being God created the ever-evolving God in the form of a sphere, that is, our original divine earth. It is a living being, an ever-changing God. He lowered the world soul into its centre. Only in a further step did he form the human souls from the world soul.
To create the world soul, he mixed the "indivisible being, which is not subject to change, and the divisible [being], which is evolving in the bodies ... and formed from both a third genus of being". These three components – indivisible being, divisible being and being from the connection between the two – he in turn mixed together several times in different proportions to form an idea. From this he formed the world soul.
The next step was the creation of man and the human soul. The eternal God put the human body together from fire, water, air and earth and provided his creation with a human soul by mixing the remaining parts of the world soul again in the same proportions as before and creating the human soul from it. He left it to the young, only conditionally immortal gods to form the body of the present human being. They surrounded the immortal soul with a mortal body and added a mortal soul with desires, passions, pain, fear, anger and senses.
Thus the immortal soul was bound to a mortal body with a mortal soul. For the immortal soul they formed the head as a spherical body, which resembled the divine earth created by God. The mortal soul, on the other hand, they separated from this divine seat through the neck and banished it to the chest. They assigned the part of the mortal soul that is eager and desires nourishment to the abdominal region. Since this area was not accessible to reason and insight, they gave the liver the gift of sight so that man could come into contact with divine truth while sleeping.
According to Plato, the human soul is thus divided into two parts: it has a divine, immortal part and an earthly, mortal part. As a rule, however, man is completely connected with the earthly, mortal part of the soul and identifies himself with it. This means that he not only follows his desires, but is also cut off from the divine world and cannot recognise it.
Plato expresses this in his famous parable of the cave, in which he depicts man sitting in a cave, bound by his legs and neck, so that his head can only look towards the back wall of the cave. The cave is illuminated by an external light source. Between the light source and the cave entrance, objects are carried past, but the person only perceives them as shadow formations. He cannot see what the things are actually like. These shadow images are the visible world for us humans. According to Plato, it is through the soul that we can attain knowledge. However, the mortal soul, which only perceives the shadow images, is not able to really recognise, but can only make assumptions.
In his line parable, Plato describes a next level of cognition. He now compares the perception of our world with the mirror images on the surface of water. At this level, man can see things more clearly and in a more differentiated way with his senses. He does not yet have any real knowledge about what he sees, but he forms opinions about it.
Only when the mortal soul turns in the direction of the spirit, of the nous, does it become a discerning soul that begins to investigate what it sees by beginning to understand the world through hypotheses and logical thinking. In doing so, man already has access to the world of ideas, the world that corresponds to the original divine life, through his connection with the spirit.In the allegory of the cave, Plato shows the attainment of the world of ideas by people leaving the cave and slowly adapting to the light of the sun. Now they can recognize the ideas that stand behind things and in this school of thought possess a higher reality than the physical things themselves. They are grasped by pure thought with the help of the immortal soul as archetypes of actual being. Moreover, at this level the soul is endowed with reason. Reason is the instance that indicates to us what is right or wrong in the sense of an inner ethical compass based on the laws of the spirit.
However, man only gains true knowledge when his soul can not only perceive the world of ideas, but can also penetrate to the unconditioned primordial ground. In this primordial ground the divine original beginning is to be found, the beginning of divine creation. Only here does the pure divine world open up to man.
According to Plato, how can man attain this knowledge of the divine creation? He must develop towards this divine world. Plato starts from the ideal-typical philosopher who turns his soul away from its entanglement with the earthly world and towards the divine soul by living virtuously, striving for the good in himself and purifying his earthly soul. As mentioned at the beginning, only the mortal soul knows pain, anger and desires. The originally divine soul dwells in the realm of the good, which Plato equates with the light of the sun in his parable of the sun. The soul is compared here with the sun. Just as only the light of the sun enables the eye to perceive objects, only the good of the soul enables the knowledge of the true world.
Thus, the realisation of the primordial ground is not about an analytical grasp, but rather a looking and dwelling in the world of ideas with a simultaneous intuitive understanding of the original creation. The realisation of the good must have become a state of being. Then the truth behind the ideas is revealed to the observer. What is meant are not ideas as we form them with our thinking. The ideas that Plato means are the actual reality. They are the living archetypes that remain, even if the individual things pass away. These include the ideas of freedom, justice, love as well as the idea of life itself and of our creation. "But those whose life is found to be thoroughly pleasing to God are the ones who do not come into contact with these subterranean places [our present location on earth] and remain freed from them as from prisons, reaching that pure abode and settling on the heights of the earth. Of these themselves, however, those who have purified themselves through philosophy live on bodilessly through all future time and attain to abodes even more glorious than those mentioned; but to describe them is not easy and not possible in the time still at hand." 
Erler, Michael, Plato, C.H. Beck Verlag, Munich 2006.
Plato, The State (Politeia), Philipp Reclam Verlag, Stuttgart 1982.
Plato, Complete Works, vol 4, Rowohlt Taschenbuch Verlag GmbH, Reinbeck bei Hamburg, 25th ed. 2019.
Plato, Of the Immortality of the Soul (Phaidon), Anaconda Verlag GmbH.
 In: Plato, Timaios, Sämtliche Werke Bd. 4, S. 33
 In: Platon, Von der Unsterblichkeit der Seele (Phaidon), S. 120