section_path: Philosophical views/Socrates and Plato
section_name: Socrates and Plato
paragraph_text: Socrates and Plato
  
  Drawing on the words of his teacher Socrates, Plato considered the psyche to be the essence of a person, being that which decides how humans behave. He considered this essence to be an incorporeal, eternal occupant of our being. Plato said that even after death, the soul exists and is able to think. He believed that as bodies die, the soul is continually reborn (metempsychosis) in subsequent bodies; however, Aristotle believed that only one part of the soul was immortal, namely the intellect (logos). The Platonic soul consists of three parts:
  
  The parts are located in different regions of the body:
  
  Plato compares the three parts of the soul or psyche to a societal caste system. According to Plato's theory, the three-part soul is essentially the same thing as a state's class system because, to function well, each part must contribute so that the whole functions well. Logos keeps the other functions of the soul regulated.
  
  The soul is at the heart of Plato's philosophy. Francis Cornford described the twin pillars of Platonism as being the theory of forms on the one hand, the doctrine of the immortality of the soul on the other. Plato was the first person in the history of philosophy to believe that the soul was both the source of life and the mind. In Plato's dialogues, the soul plays many disparate roles. Among other things, Plato believes that the soul is what gives life to the body (which was articulated most of all in the Laws and Phaedrus) in terms of self-motion: to be alive is to be capable of moving yourself, and the soul is a self-mover. He also thinks that the soul is the bearer of moral properties (i.e., when one is virtuous, it is their soul that is virtuous as opposed to, say, their body). The soul is also the mind: it is that which thinks in them. This casual oscillation between different roles of the soul in observed many dialogues, including in the Republic.
  
  Is there any function of the soul that you could not accomplish with anything else, such as taking care of something (epimeleisthai), ruling, and deliberating, and other such things? Could we correctly assign these things to anything besides the soul, and say that they are characteristic (idia) of it?
  
  No, to nothing else.
  
  What about living? Will we deny that this is a function of the soul?
  
  That absolutely is.
  
  The Phaedo most famously caused problems to scholars who were trying to make sense of this aspect of Plato's theory of the soul, such as Dorothea Frede and Sarah Broadie. 2020s scholarship overturned this accusation by arguing that part of the novelty of Plato's theory of the soul is that it was the first to unite the different features and powers of the soul that became commonplace in later ancient and medieval philosophy. For Plato, the soul moves things by means of its thoughts, as one scholar puts it, and accordingly the soul is both a mover (i.e., the principle of life, where life is conceived of as self-motion) and a thinker.