philosophy, while his pupils raised questions and argued for their views (ibid. 13, 18).
Suffering from a serious disease, in 270 Plo ̄tinos retired to Campania to die.
Porphurios divided Plo ̄tinos’ works into three periods: early, those recorded before
Porphurios’ arrival (263); middle, during Porphurios’ stay in Rome (until 268); and late,
written after Porphurios’ departure (Vit. Plot. 4–6). Porphurios reports that Plo ̄tinos, who
started to write at age 50, composed carelessly (ibid. 8) and his writings needed editorial care,
provided by both A G (ibid. 19–20) and Porphurios, Plo ̄tinos’ most loyal
students (ibid. 24). Plo ̄tinos’ work survives today in the arrangement of Porphurios’ edition
published ca 300 – 305. Porphurios arranged Plotinos’ treatises into six groups of nine trea-
tises (Enneads), because he regarded the numbers six and nine as perfect, symbolizing the
perfection of Plo ̄tinos’ philosophy. Pedagogically the arrangement guides the reader to the
heights of philosophy, the vision of the ultimate divine entity, the One. The first Ennead
treats ethics, the second physics, the third cosmology, the fourth the soul, the fifth the
intellect, and the sixth the One. Yet this division does not correspond to the treatises as
Plo ̄tinos wrote them, since sometimes Porphurios gathered his mentor’s notes (Enn. 3.9) but
more often divided longer treatises into smaller pieces (e.g. Enn. 3.8, 5.8, 5.5, 2.9)
Plo ̄tinos intended to elucidate and expound Plato’s philosophy, not to create a new one
(Enn. 5.1.8.10–14). His understanding of Plato is much indebted to earlier Platonists
especially P and Noume ̄nios, but also to Aristotle and Peripatetics like Alexander.
Plo ̄tinos tried to systematize various ideas in Plato’s work, defending them against
Peripatetic, Stoic, and other critics. For Plo ̄tinos only what subsists of its own is a sub-
stance, a hupostasis, and as such only intelligible entities qualify; but given that intelligible
entities have different degrees of unity and simplicity, there are higher and lower entities
representing different degrees of reality. Plo ̄tinos maintained the existence of three divine
hupostaseis, the One, the Intellect, and the Soul, from which everything else results.
Inspired by Plato’s Parmenides, Plo ̄tinos, like Noume ̄nios, postulated the existence of the
One, which he identified with the Form of the Good of Republic 6 and which he considered
the ultimate cause of everything in the intelligible and the sensible world. The One is
claimed to be above the Intellect, or the divine demiurge, first because the Intellect acting
under constraints, such as matter, is incompatible with the unlimited freedom that the
highest God merits; and second because an intellect implies dualism, since it has thoughts,
while the first principle must be utterly simple and united. The Intellect is characterized by
non-discursive thinking (noesis), while the Soul displays discursive or dianoetic thinking. Below
the Soul lies Nature maintained by the higher hupostaseis. The hupostaseis play a role
also in Plo ̄tinos’ cosmology. Plo ̄tinos argues for the everlastingness of the universe, the
heavens, and the heavenly bodies, which means that all of them persist and retain their
individual identity over time because they are ultimately ontologically dependent on the
World-Soul, which in turn is dependent on the Intellect. The crux of Plo ̄tinos’ philosophy is
his psychology. Plo ̄tinos seems to approach the question of how the intelligible realm relates
to the sensible one by investigating the relation between soul and body. Plo ̄tinos’ preoccupa-
tion with the soul was both metaphysical and ethical. He distinguished between inner and
outer man, and he identified man’s self with the former which is the soul. By “soul” is not
intended the embodied soul which enlivens the body, but rather the transcendent, intel-
lective one, from which the embodied emanates. Man’s aim, according to Plo ̄tinos, is to
achieve unity with the One (Enn. 1.4.3, 1.4.10).
Plo ̄tinos’ philosophy exerted enormous influence on later generations of Platonists,
leading historians of philosophy to consider Plo ̄tinos the founder of a distinct version of
PLO ̄TINOS