Platonism
From the 4th century BCE
The tradition, begun by Plato, that holds the deepest reality is not the changing world of the senses but unchanging truths grasped by reason.
The core idea
Platonists hold that behind the shifting, imperfect world we perceive there is a more real order of forms: perfect, eternal and knowable by the mind rather than the eyes. A just law or a beautiful face is just and beautiful because it shares, imperfectly, in Justice and Beauty themselves.
This gives philosophy a direction: education is a turning of the soul away from shadows towards what is real, as in the allegory of the cave. Knowledge is possible because there is something stable to know.
The tradition had a long afterlife. Neoplatonism, developed by Plotinus in the third century, shaped Christian, Jewish and Islamic thought, and modern 'platonists' in mathematics hold that numbers and sets exist independently of us.
What they hold
- Reality includes abstract, unchanging forms, not just physical things.
- Reason, not sense perception, gives us knowledge of what is most real.
- The soul is distinct from the body and can exist without it.
- The good life is ordered by reason and aimed at the Good itself.
The main criticisms
From Aristotle onwards, critics have asked how a non-physical form could explain anything about physical things, and how we could ever come to know such forms. Plato himself raised the 'third man' objection in his dialogue Parmenides. Empiricists reject the idea that reason alone can reveal reality.
“Wonder is the feeling of a philosopher, and philosophy begins in wonder.”
Plato, Theaetetus 155d, trans. Benjamin Jowett
Key figures
Where it comes up
Further reading
- EncyclopediaStanford Encyclopedia of Philosophy: Plato
- WikipediaPlatonism