ARISTOTLE
15
AKISTOTLE
eiige, aiul intelloctual knowledge is, nevertheless,
superior to sense-knowledge. How, then, docs the
mind pass from the lower knowledge to the higher?
How can the knowledge of the scnse-pcrccived {al<r-
dririv) lead to a knowledge of the iiitclligihle
(voTjri^)? Aristotle's answer is, that the mind dis-
covers the intelligible in the sense-perceived. The
minil does not, as Plato imagined, bring out of a
previous existence the recollection of certain ideas,
of which it is reminiled at sight of the phenomenon.
It brings to bear on the phenomenon a power pecul-
iar to the mind, by virtue of which it renders in-
telligible e.s.sences which are imperceptible to the
sei\se.s, because hidden under the non-essential qual-
ities. The fact is, the individual substance (first
substance) of our sense experience — (/ii'.s book, /Ai.s-
fable, thin house — hijs certam individuating ciuahties
(its particular size, shape, colour, etc.) which dis-
tinguish it from others of its species, and which alone
are perceived by the senses. Hut in the same sub-
stance, there is umlerlj-ing the individuating quali-
ties, its general nature (whereby it is a book, a table,
a house); this is the secoml substance, the Essence,
the Universal, the Intelligible. Now, the mind is
endowed with the power of abstraction, generaliza-
tion, or induction (.Vristotle is not very dear jis to
the precise nature of this power) by which it removes,
.so to speak, the veil of particularizing qualities and
thus brings out, or leaves revealed, the actually in-
telligible, or universal, element in things, which is
the object of intellectual knowledge. In this tlieory,
intellectual knowledge is developed from sense-knowl-
edge in so far as that process may be called a de-
velopment in which what was only jiotentially in-
telligible is rendered actually intelligible by the
operation of the active intellect. The t'niversal was
in re before the human mind began to work, but it
was there in a manner only potentially because, by
reason of the individuating qualities which enveloped
it, it W!us only potentially intelligible. Aristotle's
theory of universals. therefore, is that (I) The Uni-
versal does not exist ajjart from the particular, as
Plato taught, but in particular things; (2) The Uni-
versal :us such, in its full-blown intelligibility, is the
work of the mi.id, and exists in the mind alone,
though it has a foundation in the jxitentially univer-
sal e.ssence which exists independently of the mind
and outside the mind.
II. TiiEOHKTic.vL Philosophy. — (1) Metaphysics. — Metaphysics, or, more properly. First Philo.sophy, is the Science of Being as Being. That is to say, although all sciences are concerne<l with being, the other sciences are concerned only with part of real- ity, while this science contemplates all reality; the other sciences seek proximate and particular causes, while this science seeks the ultimate ami universal cau.ses; the other sciences study being in its lower determinations (quantity, motion, etc.), while this science studies Bemg as such, that is. in its highest determinations (substance, cause, goodness, etc.). The mathematician claims that a certain object comes within the scope of his science if it is circular, or square, or in any other way endowed with quantity. Similarly, the |)hysicist claims for his .science whatever is endowed with motion. For the metaphysician it is sufficient that the object in question be a being. Like the Inmian -soul or (!od, the object may be devoid of quantity, and of all physical motion; yet .so long as it is a being, it comes within the scope of metaphysics. The principal question, then, in First Philo.sophy is: What are the ultimate principles of Being, or of re- ality as Being? Here .Aristotle passes in review the opinions of all his predece.s.sors in Greek Philo.sophy, from Thales to Plato, showing that each successive answer to the question just quoted was somehow defective. He devotes special attention to the Pla- tonic theory, according to which ideas are the ul-
timate principles of Being. That theory, he contends,
was introduced to explain how things are, and how
things arc known ; in ootli respects, it is inadequate.
To postulate the existence of ideas apart from things
is merely to complicate the problem; for, unless the
ideas have some definite contact with things, they
cannot explain how things came to be, or how they
came to be known by us. Plato docs not maintain
in a definite, scientihc way a contact between ideas
and phenomena; he merely takes refuge in expres-
sions, such as participation, imitation, which, if they
are anything more tiian empty metaphors, imply a
contratliction. In a word, Aristotle believes that
Plato, by constituting ideas in a world separate from
the world of phenomena, precluded the possibility
of solving by means of ideas the problem of the
ultimate nature of reality. What, then, are, accord-
ing to Aristotle, the principles of Being? In the
metaphy.sical order, the highest determinations of
Being are .\ctuality (^rrtX^x"") and Potentiality
(iivaiut). The former is perfection, realization,
fullness of Being; the latter imi>erfection, incomplete-
ness, perfectibility. The former is the determining,
the latter the determinable principle. Actuality and
potentiality are above all the Categories; they are
found in all beings, with the exception of the Sui)reme
Cause, in Wlioni there is no imperfection, and, there-
fore, no potentiality. He is all actuality, Actus
Purus. .\\\ other beings are composed of actuality
and potentialitv, a dualism which is a general meta-
iihysical formula for the tlualism of matter and form,
body and .soul, substance and accitlent, the soul ancl
its faculties, passive and active intellect. In the
physical order, potentiality and actuahty become
Matter and Form. To these are to be added the
Agent (Efficient Cause) and the End (Final Cause);
but as the efficiency and finality are to be reduced,
in ultimate analysis, to Form, we have in the phys-
ical order two ultimate principles of Being, namely,
Matter and Form. The four generic causes. Material,
Formal, Elficient, and Final, are .seen in the case,
for instance, of a statue. The Material Cause, that
nut of which the statue is made, is the marble or
bronze. The Formal Cause, that according to vhich
the statue is made, is the idea existing in the first
place as exemplar in the mhid of the sculptor, and
in the second place as intrinsic, determining cause,
embodied in the matter. The F.tficient Cau.se. or
Agent, is the sculptor. The Final Cause is that
for the sake of which (as, for instance, the price paid
the sculptor, the desire to please a patron, etc.) the
statue is made. .Ml these are true causes in so far
as the effect depends on them either for its existence
or for the mode of its existence. Pre-.Aristotelean
philosopliv either failed to discriminate between the
different kinds of causes, confounding the material
with the ethcient principle, or insisted on formal
causes alone as the true principles of Being, or. rec-
ognizing that there is a principle of fin.ality, hesitated
to apply that principle to the details of the cosmic
process. Aristotelean philosophy, by discriminating
oetween the different generic cau.ses and retaining,
at the .same time, all the different kinds of causes
which played a part in previous systems, marks a
true development in metaphysical speculation, and
.shows itself a true .synthesis of Ionian, Eleatic, So-
cratic, Pythagorean, and Platonic philosophy. A
jMiint which should be emphasized in the exix>sition
of this portion of Aristotle's philosophy is the doc-
trine that all action consists in bringing into actual-
ity what was somehow potentially contained in the
material on which the agent works. This is true
not only in the world of living things, in which, for
example, the oak is jiotentially contained in the acorn,
but also in the inanimate world in which heat, for
instance, is potentially contained in water, and needs
but the agency of fire to be brought out into actual-
