Plato’s theory of ideas. A simple and detailed summary of philosophy.
Plato develops the theory of ideas to deepen the concept of science, placing it as a conceptual and absolute knowledge that goes beyond sophistic relativism. Plato’s ideas are subsisting metaphysical entities to which Plato confers all the characteristics of being Parmenidean (except uniqueness). Ideas reside in Hyperuranium. Hyperuranium is a transcendental and aspatial region (compared to Dante’s empyrean or Christian paradise) where the soul also originates.
For Plato, things belonging to sensible reality are nothing but imperfect copies of ideas, which thus become the unique and perfect models of the multiple and imperfect things of this world. From these considerations, Plato comes to support the dualistic perspective of both knowledge and being: opinion, the lower degree of knowledge, leads us to an imperfect truth, having as its object of study the imperfect things of sensitive reality; science, on the other hand, leads us to perfect and immutable truth, having ideas as its object of study.
But what is the link between ideas and things? Ideas are the criterion for judging things, or the condition of thinkability of objects (for example, let’s say that two things are equal on the basis of the idea of equality); but ideas are also the causes of things, that is, the models that things imitate or with which things participate (for example, let’s say that two individuals are men, as they both participate in the idea of man, which arises as a cause so they are men, not women).
In the final analysis, three different types of relationship between ideas and things are thus configured:
Mimèsi: so things imitate ideas
Metèssi: for which things participate, albeit to a limited extent, in the essence of ideas
Parusìa: whereby ideas are present in things
In the stage of maturity, Plato develops a hierarchy that orders ideas within Hyperuranium:
the ideas-values, corresponding to the supreme ethical, aesthetic and political principles (Good, Beauty, Justice, etc.);
mathematical ideas, corresponding to mathematical entities and principles (the equal, the square, etc.);
the ideas of natural things, such as the idea of man;
ideas of artificial things, such as the idea of bed.
The Platonic ideas thus weave a “plot” of essences having a hierarchical-pyramidal order, with the ideas-values at the top and the idea of Good at the top, which surpasses all the others for “value and power”, but it does not create them (therefore the association of Good with a person-creator god is absent).
Having clarified all the characteristics of the ideas, Plato must explain the way in which man manages to access knowledge of them. Plato, therefore, resorts to the doctrine-myth of the anamnesis, or of the reminiscence, that is, of the memory: as previously said, the soul originates in Hyperuranium, where it resides contemplating ideas until it is embodied in our body . This contemplation is transferred to us as a dormant memory which resurfaces gradually thanks to the experience of things. All this leads to consider human knowledge a form of innatism, being knowledge based on ideas (or “meters” of judgment) always present in the knowing subject, and not based on sensitive experience (empiricism).