Plato’s theory of forms (or ideas)

Theory developed by Plato (c.427-c.347 BC) in his middle-period dialogues (especially Phaedo, Symposium, Republic) and criticized by himself in his Parmenides (see third man argument). The language of the theory occurs in his earlier dialogues, but its interpretation is disputed, as is his reaction in later dialogues to the Parmenides criticisms: did he modify the theory, abandon it, or treat the criticisms as applying only to a distorted version of it?

Forms (usually given a capital F) were properties or essences of things, treated as non-material abstract, but substantial, entities. They were eternal, changeless, supremely real, and independent of ordinary objects which had their being and properties by ‘participating’ in them.

But Plato puzzlingly treated them as both universals (see Platonism), suggesting they were immanent in things, and paradigms (see paradigmatism), suggesting they were transcendent and themselves had the properties they represented: Beauty is beautiful (but Change changes – despite being, as a Form, unchanging). Aristotle (384-322 BC) too believed in forms (with a small F), but no longer as transcendent objects. ‘Idea’ is a misleading synonym for ‘Form’; Forms were objects of knowledge but in no way themselves mental or in the mind.

Also see: one over many principle

Source:
W D Ross, Plato’s Theory of Ideas (1

Plato (/ˈpleɪtoʊ/ PLAY-toe;^[2] Greek: Πλάτων Plátōn, pronounced [plá.tɔːn] in Classical Attic; 428/427 or 424/423 – 348/347 BC) was an Athenian philosopher during the Classical period in Ancient Greece, founder of the Platonist school of thought and the Academy, the first institution of higher learning in the Western world.

He is widely considered the pivotal figure in the history of Ancient Greek and Western philosophy, along with his teacher, Socrates, and his most famous student, Aristotle.^[a] Plato has also often been cited as one of the founders of Western religion and spirituality.^[4] The so-called Neoplatonism of philosophers like Plotinus and Porphyry greatly influenced Christianity through Church Fathers such as Augustine. Alfred North Whitehead once noted: “the safest general characterization of the European philosophical tradition is that it consists of a series of footnotes to Plato.”^[5]

Plato was the innovator of the written dialogue and dialectic forms in philosophy. Plato is also considered the founder of Western political philosophy. His most famous contribution is the theory of Forms known by pure reason, in which Plato presents a solution to the problem of universals known as Platonism (also ambiguously called either Platonic realism or Platonic idealism). He is also the namesake of Platonic love and the Platonic solids.

His own most decisive philosophical influences are usually thought to have been along with Socrates, the pre-Socratics Pythagoras, Heraclitus and Parmenides, although few of his predecessors’ works remain extant and much of what we know about these figures today derives from Plato himself.^[b] Unlike the work of nearly all of his contemporaries, Plato’s entire body of work is believed to have survived intact for over 2,400 years.^[7] Although their popularity has fluctuated over the years, Plato’s works have never been without readers since the time they were written.