Ancient philosophy The Academy Platonism was originally expressed in the
dialogues of Plato, in which the figure of
Socrates is used to expound certain doctrines, that may or may not be similar to the thought of the historical
Socrates, Plato's master. Plato delivered his lectures at the Platonic Academy, a precinct containing a sacred grove outside the walls of
Athens. The school continued there long after Plato's death. There were three periods: the Old, Middle, and New Academy. The chief figures in the Old Academy were
Speusippus (Plato's nephew), who succeeded him as the head of the school (until 339 BC), and
Xenocrates (until 313 BC). Both of them sought to fuse
Pythagorean speculations on
number with Plato's theory of forms.
The Skeptical Academy Around 266 BC,
Arcesilaus became head of the academy. This phase, known as the
Middle Academy, strongly emphasized
philosophical skepticism. It was characterized by its attacks on the
Stoics and their
assertion of the certainty of truth and our knowledge of it. The
New Academy began with
Carneades in 155 BC, the fourth head in succession from
Arcesilaus. It was still largely skeptical,
denying the possibility of knowing an absolute truth; both
Arcesilaus and
Carneades argued that they were maintaining a genuine tenet of
Plato.
Middle Platonism Around 90 BC,
Antiochus of Ascalon rejected skepticism, making way for the period known as
Middle Platonism, in which Platonism was fused with certain
Peripatetic and many
Stoic dogmas. In Middle Platonism, the Platonic Forms were not transcendent but immanent to rational minds, and the physical world was a living, ensouled being, the
World-Soul. Pre-eminence in this period belongs to
Plutarch. The eclectic nature of Platonism during this time is shown by its incorporation into
Pythagoreanism (
Numenius of Apamea) and into
Jewish philosophy (
Philo of Alexandria).
Neoplatonism , have been influenced by Platonism. In the third century,
Plotinus recast Plato's system, establishing
Neoplatonism, in which Middle Platonism was fused with
mysticism. At the summit of existence stands
the One or the Good, as the source of all things. It generates from itself, as if from the reflection of its own being, reason, the
nous, wherein is contained the infinite store of ideas.
St. Augustine was heavily influenced by Platonism as well, which he encountered through the Latin translations of
Marius Victorinus of the works of
Porphyry and/or
Plotinus. Meanwhile, Platonism influenced various philosophers such as at the
School of Chartres.
Christoplatonism is a term used to refer to a
dualism opined by Plato, which holds
spirit is good but
matter is evil, which influenced some
Christian churches, though the Bible's teaching directly contradicts this philosophy and thus it receives constant criticism from many teachers in the Christian Church today. According to the
Methodist Church,
Christoplatonism directly "contradicts the Biblical record of God calling everything He
created good." . This
modern Platonism has been endorsed in one way or another at one time or another by numerous philosophers, such as
Bernard Bolzano, who argue for anti-
psychologism. Plato's works have been decisively influential for 20th century philosophers such as
Alfred North Whitehead and his
Process Philosophy; and for the critical realism and metaphysics of
Nicolai Hartmann.
Analytic In contemporary philosophy, most Platonists trace their ideas to
Gottlob Frege's influential paper "
Thought", which argues for Platonism with respect to propositions, and his influential book,
The Foundations of Arithmetic, which argues for Platonism with respect to numbers and is a seminal text of the
logicist project. and
Peter van Inwagen.
Iris Murdoch espoused Platonism in
moral philosophy in her 1970 book
The Sovereignty of Good.
Paul Benacerraf's
epistemological challenge to contemporary Platonism has proved its most influential criticism.
Continental In contemporary
Continental philosophy,
Edmund Husserl's arguments against psychologism are believed to derive from a Platonist conception of logic, influenced by Frege and his mentor Bolzano.—Husserl explicitly mentioned Bolzano,
G. W. Leibniz and
Hermann Lotze as inspirations for his position in his
Logical Investigations (1900–1). Other prominent contemporary Continental philosophers interested in Platonism in a general sense include
Leo Strauss,
Simone Weil, and
Alain Badiou. == Influence on religions ==