de Anima 3.4
Turning now to the part of the
with which the soul knows and (whether this is separable from the
others in definition only, or spatially as well) we have to
what differentiates this part, and how thinking can take place.
If thinking is like perceiving, it must be either a process in
the soul is acted upon by what is capable of being thought, or a
process different from but analogous to that. The thinking part of
soul must therefore be, while impassible, capable of receiving the
of an object; that is, it must be potentially identical in
with its object without being the object. Thought must be related
what is thinkable, as sense is to what is sensible.
Therefore, since everything is a possible object of thought, mind,
order, as Anaxagoras says, to dominate, that is, to know, must be
from all admixture; for the co-presence of what is alien to its
is a hindrance and a block: it follows that it can have no nature
its own, other than that of having a certain capacity. Thus that
soul which is called thought (by thought I mean that whereby the
thinks and judges) is, before it thinks, not actually any real
for this reason it cannot reasonably be regarded as blended with
body; if so, it would acquire some quality, e.g. warmth or cold,
even have an organ like the sensitve faculty: as it is, it has
was a good idea to call the soul 'the place of forms', though this
description holds only of the thinking soul, and even this is the
only potentially, not actually.
Observation of the sense organs and their employment reveals a
distinction between the impassibility of the sensitive faculty and
of the faculty of thought. After strong stimulation of a sense we
less able to exercise it than before, as e.g. in the case of a
sound we cannot hear easily immediately after, or in the case of a
bright color or a powerful odor we cannot see or smell, but in the
of thought thinking about an object that is highly thinkable
more and not less able afterwards to think of objects that are
thinkable; the reason is that while the faculty of sensation is
dependent upon the body, thought is separable from it. De
Aristotle thought that in perceiving some perceived object, our
perceptive organ receives the form of the perceived object, but not
matter. So when we see white, our sight organs receive the form of
white but do not receive white matter. So too, when we use our mind
think about or understand some object, our mind takes on the form of
the object. He says that our intellect takes on the quality of the
object potentially, but not actually. He does not
seem to have thought that there was any organ of the intellect.
sight has eyes, the intellect has no bodily organ.
Because intellect must be able to take on any quality, Aristotle
concludes that it itself can have no particular quality. In other
words, the intellect cannot actually be anything, but it must
potentially be everything it can understand (and yet remain
potential!). It cannot be mixed with the body, for then it would
the qualities of the body it was mixed with.
To understand what Aristotle may be talking about, take a house and
blueprint of a house: the house itself has a form, and that form is
"the same" as the form present in the blueprint. The blueprint has
form of the house, but none of the matter. In analogous fashion, the
mind takes on the form of what it thinks about, but none of the
The blueprint has the form of the house, but remains only
house (it is not actually a house). Just so, the mind has the form
the object of thought, but is not actually that object.
Now take a piece of pure white paper: you can depict anything on it
that is capable of 2 dimensional depiction except something
that is entirely the same color as the paper. I suppose you can
depict even that negatively: that is to say, by coloring in
everywhere except for the depiction of the object.
There is a problem (only one?) with the theory: when bronze changes
from an ingot into a
statue, the underlying stuff, bronze, is the sort of stuff that can
an ingot or a statue. Bronze cannot become "the action of batting a
baseball" or "watery iridescence" or "father of Sam." In other
when things change, on Aristotle's version of change, the underlying
matter is said to lose one form and acquire another form, but the
underlying matter must be such as to acquire that sort of form. What
kind of thing must intellect be in order to be capable of acquiring,
even merely potentially,
absolutely everything that is thinkable (such as "bronze," "watery
iridescence," "kick my foot thru that door," "my mummy's mum's mum"
any other thought of whatever form)?
Whatever intellect is, it seems a lot like prime matter. That is, it
psychic prime stuff, because it is not anything in actuality, but it
capable of acquiring every form (in the way that a blueprint
the form of a house).
Aristotle does not think that the soul survives the body, nor that
body survives the soul. At most, he may think that the intellect
survives the body. But note that there is no good reason to think
Aristotle thinks or should think that whatever survives has anything
like a personality: Joe's intellect may
survive, but it is no longer identifiable as Joe's. It is rather
just intellect in
something like the way that the bronze that made up a cannon may be
reformed into a porpoise statue and then a bunch of bronze pellets
What is more, human souls qua souls are not different from each
according to Aristotle (well, according to the prevailing view of
Aristotle). Thus your soul is the same as my soul. The only
difference is a difference "in number," by which is meant that our
souls are two souls, not one soul, and so each one is not the other
(if they were not different in number, there would be only one soul
between the two of us).
In all, this chapter highlights some deep problems for Aristotle's
theory of knowledge.