Platonic dualism in philosophy and metaphysics

Platonic Dualism

Although Plato is a major figure in the history of philosophy and a comparatively large number of his works have been preserved, it is important to place him in his proper historical context in order to address certain elements of his philosophy, such as Platonic Dualism. Platonic Dualism is Plato's solution to the problem of changeability -- the basic philosophic issue of, in Soccio's words, "explain[ing] how one kind of thing changes into another," which "generate[s] ambiguities and seeming contradictions" (Soccio 127). Can we really say that a human being, when 6 weeks old, is actually the "same" as the same walking and talking human being at the age of thirty years?

These issues were raised by numerous Greek philosophers and proto-scientists long before Socrates conversed in the Agora and Plato wrote the Dialogues -- this loose grouping of Greek philosophers, whose works are preserved mostly in fragments, are known as the "Presocratics" and two of them -- Parmenides and Heraclitus -- are extremely influential on Plato in developing Platonic Dualism.. Plato had to accept certain statements that had been laid out by these two earlier philosophers in order to construct his own philosophical system. What Plato acknowledges from Heraclitus and Parmenides are aspects of their attempt to define the unity of things. For Heraclitus it was the notion of constant change -- Heraclitus is famous for the pithy observations that "you cannot step in the same river twice" and "everything flows" -- but for him change occurs in some sort of orderly cycle. Parmenides replaces Heraclitus's emphasis on change with an emphasis on being: he considered unity to rely in the mere fact of being, and considered being itself to be "perfect and material and whole" because "it cannot move or change," among other reasons (Soccio 126).

Plato takes the worldviews of these two Presocratic philosophers and puts them together. He asks us to consider whether the unity envisaged by the Presocratics is, in fact, not a single reality, and if the two individual monisms of Parmenides and Heraclitus could be considered a single dualism. In other words, Plato asks what if there were two realities: one eternal and changeless (as Parmenides saw reality), the other in constant flux (as Heraclitus saw it)? This is the basic idea of Platonic Dualism but that makes it sound simplistic, when in fact it opens up a host of new epistemological and metaphysical issues. For example, Plato points out that a truly Heraclitan reality would be "devoid of the possibility of knowledge and certainty" -- it becomes a world of continually changing appearances and no substance (Soccio 127). So Plato is able to define Heraclitan reality as something that needs to be termed "becoming" rather than being, because things like permanent knowledge or truth are not to be found within it. Plato's antagonism towards the philosophical position of the Sophists was spurred by their ability only to attend to this superficial Heraclitan "becoming" -- the real truth and knowledge that philosophers seek must exist beyond in a kind of eternal perfect unity, a Parmenidean monism that exists beyond the Heraclitan flux.