Anthony Kenny Aquinas on Mind

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the soul alone, but of the soul-body compound& . Aristotle agreed
with Democritus that the activities of the sense-faculties are
caused by the action of empirical objects upon the senses.& But
he held that the intellect does have an activity in which the body
has no share. Now nothing corporeal can have an effect on what
is incorporeal. Hence, the cause of intellectual activity must
involve more than a mere stimulus from empirical bodies.
(S 1, 84, 6c)5
The something more is of course the agent intellect, which we have
already encountered, whose function is to make phantasmata received
from the senses, by abstraction, into actually thinkable objects. Hence
sense-perception is not the total and complete cause of intellectual
knowledge; it is rather, says Aquinas, in some manner the matter of
the cause .
The ideas of the intellect are abstracted, then, from phantasms
(phantasmata). A visual image, called up when one s eyes are shut;
the words one utters to oneself sotto voce in the imagination: these
are clearly examples of what he means by phantasm . How much
else is covered by the word is difficult to determine. Sometimes
straightforward cases of seeing events in the world with eyes open
seem to be described as a sequence of phantasmata: it is not clear
whether this means that the word is being used broadly to cover any
kind of sense-experience, or whether Aquinas held a regrettable theory
that external sense-experience was accompanied by a parallel series
of phenomena in the imagination. For our purposes it is not necessary
to decide between these alternatives: when Aquinas talks of
phantasms we can take him to be speaking of occurrences taking
place either in the sense or the imagination. For what he is anxious
to elucidate is the role of the intellect within the sensory context
provided by the experience of the sentient subject.
Aquinas frequently insists that phantasms play a necessary part
not only in the acquisition of concepts, but also in their application.
During our mortal life, he says, it is impossible for our intellect to
perform any actual exercise of understanding (aliquid intelligere in
actu) except by attending to phantasms.
When a concept has been acquired, or when a belief has been
94 Aquinas on Mind
formed, the intellect has taken a step from potentiality towards
actuality; it is no longer a tabula rasa, but has a content; it is in
possession of ideas or species. But this, according to Aquinas, is not
sufficient to enable the intellect to operate unaided: phantasms are
needed not only for gaining possession of species but also for making
use of them.
Why so? Aquinas puts to himself the following objection:
It would seem that the intellect can exercise intellectual activity
without turning to phantasms, simply by using the species in its
possession. For the intellect is placed in a state of actuality by a
species informing it. But for the intellect to be in a state of
actuality is precisely for it to exercise intellectual activity.
Therefore species suffice to enable the intellect to exercise
intellectual activity without turning to phantasms.
(S 1, 84, 7 obj. 1)6
The answer is to be found by attending to the distinction between
two stages of actuality. Possessing a concept or a belief is different
from being totally uninformed; but it is different again from exercising
the concept or calling the belief to mind. I may know French without,
on a given date, speaking, reading or thinking in French; I may believe
that the earth is round even when my thoughts are on totally different
things. The distinction, in terms of actuality and potentiality, may be
made in more than one way. Knowing French is an actuality by
comparison with the state of the newborn infant; it is a potentiality
by comparison with the activity of actually speaking French. As has
been said, the three stages can be distinguished as pure potentiality,
first actuality, and second actuality. In these terms, the thesis of 1,
84, 7 is that phantasms are needed not only to take the intellect from
potentiality to first actuality, but also from first actuality to second.
Without the jargon, the thesis is that intellectual thought is impossible
apart from a sensory context.
Aquinas offers two proofs of this thesis. First, although the intellect
has no organ of its own, the exercise of intellect may be impeded by
injury to the organs of the imagination (as in a seizure) or of memory
(as in a coma). Such brain damage prevents not only the acquisition of
new knowledge, but also the utilization of previously acquired
knowledge. This shows that the intellectual exercise of habitual
knowledge requires the cooperation of imagination and other powers.
Second, he says, everyone can experience in his own case that when he
Sense, imagination and intellect 95
tries to understand something, he forms some phantasms for himself
by way of examples in which he can so to speak take a look at what he
is trying to understand. Similarly when we want to make someone
understand something, we suggest examples to him from which he can
form his own phantasms in order to understand (1, 84, 7).
A metaphysical reason is offered to explain this. The proper object
of the human intellect in the human body is the quiddity or nature
existing in corporeal matter . The quiddities of corporeal things must
exist in corporeal individuals.
Thus, it is part of the concept of a stone that it should be
instantiated in a particular stone, and part of the concept of a
horse that it should be instantiated in a particular horse, and so
on; so the nature of a stone or of any material thing cannot be
completely and truly known unless it is known as existing in the
particular; but the particular is apprehended by the senses and
the imagination. Consequently, in order to have actual
understanding of its proper object, the intellect must turn to
phantasms to study the universal nature existing in the
particular.
(S 1a, 84, 7)7
Several things are noteworthy about this whole argument. First, it
starts from the premise that there is no bodily organ of the intellect.
One might be inclined to ask: how does St Thomas know that brain
activity is not necessary for thought, even for the most abstract and
intellectual thought? Second, these two possible lines of answers
suggest themselves. The first is that St Thomas would agree that
there is not in fact, in this life, any thought, however exalted, which
is not accompanied by brain activity. But he would say that this was
precisely because there was no thought, however exalted, which is
not accompanied by the activity of the imagination or senses. The
second is that even if brain activity is a necessary condition for
thought, this does not make the brain an organ of thought in the
way that the eyes are the organ of sight and the tongue and palate
are organs of taste. An organ is, as its etymology suggests, something
like a tool, a part of the body which can be voluntarily moved and
used in characteristic ways which affect the efficiency of the
discriminatory activity which it serves. The difficulty is that these
two answers seem to cancel out. In the sense of organ in which
there is no organ of thought, there is no organ of imagination
96 Aquinas on Mind
either I cannot move my brain in order to imagine better in the
way that I can turn my eyes to see better. We may use organ in a
broad sense, to mean any part of the body which is intimately related
to the exercise of a faculty, so that, in this sense, the visual cortex
would be an organ of sight no less than the eye. If so, why should we [ Pobierz całość w formacie PDF ]

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