1. Plato.
The two basic premises of Plato's doctrine
of the immortality of the
soul are a radical dualism
which sees man as a composite of a material body
and
an incorporeal soul, and the assertion that the soul,
and not the
body, is the essential, the true man. The
soul is not only totally
independent of the body, but
it is of divine origin and only an unwilling
guest in
the body. This is what makes Plato define death as a
liberation of the soul from the bodily “prison.” The
probable source of this view is the Orphic “soma-
sema,” the body is the prison (of the soul).
Whether
it is this view of the soul which leads to the notion
that the
soul is the essential person or the other way
around, is impossible to
determine. In any case, when
Crito asks Socrates how he wants to be buried,
the
latter expresses surprise that his listeners apparently
still did
not get the main point of his discussion,
namely, that it is the Socrates
who is now conversing
with them, and not the corpse he will soon
become,
who is the real Socrates (Phaedo 115C-D).
Plato advances the following arguments for the
immortality of the soul: (1)
the argument from remi-
niscence. Man has
certain ideal concepts as well as
some knowledge of a
priori (e.g., mathematical) truths
which could not have been
derived or been acquired
through experience (Phaedo
72A-77A; Meno 81B-86B).
Thus we must have acquired
them before this life
began, which indicates that the soul is prior to
the
body. But this would prove only the preexistence of
the soul, not
its immortality, although the latter is made
more plausible if preexistence
is true. The case for
immortality is strengthened, however, when we con-
sider that in order to apprehend the eternal
“Ideas”
or “Forms,” the soul
must itself be eternal for “noth-
ing
mortal knows what is immortal.”
(2) Argument from the “fact” that the soul is the
principle of life: the soul, whose essence is life (vitality)
and thus the
very opposite of death, cannot be con-
ceived
as dying any more than fire can be conceived
as becoming cold. This
argument (Phaedo, 100B-107A)
is based on Plato's
arbitrarily equating “soul” as the
principle of life
with soul as the bearer or originator
of mental and emotional activity.
Moreover, to hold
that as the principle of life the soul is the
“Idea” of
life and, as such, deathless and eternal
has no bearing
on the immortality of the individual soul, since the
“Idea” of a thing is, according to Plato himself,
very
different from its individual manifestation.
The same unwarranted equation of the two meanings
of soul underlies the
third argument, (3) the soul as
self-moving, which states that since the
soul moves
itself and is the source of movement and life, it must
be
immortal because that which moves itself is incor-
ruptible and ingenerable (Phaedrus 245C-246A).
(4) The soul as “simple.” Plato argues that the soul
must be immortal since it is “simple” and
incorporeal.
An incorporeal substance is “naturally”
incorruptible,
and “simple” means that it is
uncompounded and
therefore incapable of dissolution (in the sense of
falling
apart; Kant has later argued that even if it has no
“extensive quality,” it nevertheless possesses
“intensive
quality” and can therefore dwindle to
nothingness “by
a gradual loss of power”).
Plato himself was well aware of the inadequacy of
his arguments for the
immortality of the soul (and this
may be taken as a proof that he never
doubted its
truth). He admitted that the divine origin of the soul
as
well as the existence of eternal “Ideas” require
further investigation (Phaedo 107B). His former
pupil,
Aristotle, rejected these basic assumptions on which
Plato's
doctrine of immortality of the soul rested.
Aristotle held that the soul is
one with the body as
its “form” (which term is quite
different from Platonic
sense of “Form” or
“Idea”). There is no necessity for
the separate existence of Ideas, because “the shape
of
a bronze sphere exists at the same time as the bronze
sphere
exists,” but it is not at all certain that “any form
survives afterwards” and “the soul may be of this
sort”
(Metaphysics 1070a).
But while he was quite positive in his denial that
the soul could survive in
its entirety, Aristotle spoke
of the possibility of survival of the
intellectual part
of it. Unfortunately, it is not at all clear what he
meant
by the term “pure intellect”: on the one hand
he
described it as a capacity, but then there are passages
where he
speaks of it as if it were an incorporeal
substance. Clearly, only the
latter could be conceived
as immortal. What Aristotle may have had in
mind
is that if not the whole soul, then at least man's active
intellect is of divine origin (since he spoke of it as
coming from the
“outside”) and as such can be said
to be eternal. But
this is not the immortality of the
soul as Plato conceived it. Not only
does Aristotle seem
to be contemptuous of this doctrine (Nicomachean
Ethics 1111b), but most of his commentators
beginning
with Alexander of Aphrodisias, and particularly Aver-
roës, were of the opinion that
“The Philosopher” did
not believe in any kind of
individual immortality.