above the latter. Plato and Aristotle made out ethics to be
a department of politics. This was because the Greeks, in a
highly developed political system within a small territory, were
politicians first and moralists afterwards. Only a few saw
that there was room for a further consideration of man's action
as man and not as citizen. When Greek political life became
extinct the ethical question in turn came uppermost, e. g. in



xix.] Elements of General Philosophy. 199

Stoicism and Epicureanism, in which ethics began to be
differentiated as a theory of individual action. At a time
when the traditional religious conceptions had lost their hold
on cultivated minds, it became of primary importance that
some Theory of Life and Conduct should be developed as
a substitute for a religious creed. With the progress of time
a more highly analytical study of human nature has arisen,
hence we distinguish more sharply between ethical and
political principles.

Ethics and Christianity.

Again, the influence of Christianity on ethics is extremely
marked. Christianity inculcated the notion of the individual
life or soul as having infinite value. The man, in and for
himself, once swamped in the citizen, has become the fact of
greatest moment. What a man is and what a man ought to do
are questions that have become prominent in the Christian
era as they never did in Greek or Roman civilisation.

E-hics and Theology. Cogency of the Social Factor.

In so far as ethics has helped to develop ethical principles,
it has done so inevitably in relation to certain theological
considerations. Yet this does not make ethics necessarily
dependent upon theology. One ought to be able to determine
the rule of life merely from a consideration of human nature.
Morality proper depends upon the exclusion of theology. To
seek a constraining power in order to good conduct impeaches
the very notion of morality and trangresses the province of
ethics. Morality can only give intelligible reasons. Con-
science, the impulse to do right from a purely ethical point
of view, arises from the fact that man is no mere individual
but a member of the social organism. What a man becomes,
he becomes not of himself but through others. Therefore,



200 Elements of General Philosophy.

while it is natural that he should act out of regard to self
wnreflectively, when his actions begin to be done reflectively,
it is impossible for him not to allow that he is bound to
sacrifice himself in all cases where there is a conflict between
self-interests and the common good. There is a law upon
him not to be thrown off. Not to allow this is for a man
to claim to have created, by and for himself, life and know-
ledge and all that makes life worth having.



PART II.

SPECIAL LECTURES
LECTURE XX.

ON THE EPISTEMOLOGY OF PLATO IN THE
PHMDO, REPUBLIC, THEMTETUS AND TIMMUS\

READING Plato's Dialogues, Jowett's Translation; Plato's Titnaus,
edited by Archer-Hind.

THE stages in Plato's life are well marked. The date
of his birth being B.C. 427, we note (a) the Socratic stage
(407-399) his Lehrjahre as they have been called when he
was the pupil of Socrates till the latter was put to death.
(3) Twelve years of travel (399-387) his Wanderjahre when
he visited Magna Grsecia (S. Italy), Sicily, Egypt, with
occasional returns to Athens, when he began his relations
with Dionysius of Syracuse, and which include his first
period of productive activity (i. e. of the Socratic dialogues).
(c] The stage of supreme effective thinking and teaching,
as a philosopher, with his school in the grove of Academus
(387-367). (<f) To Syracuse again, visiting the younger

1 From a special course on the T/iate(us,&c., February, March, 1892.



202 Elements of General Philosophy. [LECT.

Dionysius (367-365). In 361 he visited Syracuse yet again.
(<?) Third period of philosophising and teaching, during
which he gave the last development to his theory of ideas,
and his cosmology. The chief productions of this period
were the Laws, probably the Philebus, the Parmem'des, and
the Sophistes, leading up to the Tim&us.

We have already seen (supra, Lecture IV) what was the
heritage of thought to be entered into by Plato : first, the
physical philosophy of the Pre-Socratics ; then in Protagoras
a despair of physical and also of moral science, withal
a highly refined argumentation as to practical life ; next the
teaching of Socrates, also despairing of physical science,
but aiming at a science of moral conceptions and identifying*
virtue with knowledge, or with the outcome of knowledge.
Into the mind of his predecessors and contemporaries Plato
entered generally, combining the high moral purpose of
Socrates, and, at first, the Socratic method with a wider and
bolder sweep of constructive thinking. He asked, in its
widest generality, as the great question for a philosopher,
What is knowlege? Though ethical purpose is always
present as his final aim, yet the problem of conduct was to
be solved by him through previous consideration of the
universal problem of knowledge, and not of knowledge in
a limited sphere as with Socrates.

The Theatetus is a dialogue of research without the
positive results characterising the Republic. Many points
are raised, but not settled. The subject is of the greatest
difficulty, and one on which Plato's writings show a con-
tinuous development. It is occupied with epistemology
\\ith knowledge as such here treated more independently
than elsewhere of his dogmatic theory of Ideas. It sums
up and destructively criticises all previous views on the



XX.] Elements of General Philosophy. 203

problem of knowledge, making reference, explicit or im-
plicit, to Plato's predecessors. His own theory it leaves
indeterminate. Had he thought out a reasoned solution, his
positive philosophy would have been complete. Some
suppose the dialogue was written before 367, but revised in
the third period, because of the view that philosophers
should stand aloof from practical life. This, it is said, will
have been in connexion with his unfortunate experiences
during his later visits to Syracuse and his own isolation from
practical life. On the other hand, the Laws, his latest work,
shows the philosopher in close relation with practical life.

The Republic is Plato's greatest achievement in its com-
bination of range of thinking with literary effect. Close
inspection, however, shows signs of aggregation at different
times. Books I and II on Justice are quite Socratic, and
may well have been written in his first period of pro-
duction. After Book I, which leads to no positive result,
\ve have two great divisions: (i) a complete political theory
(II-IV and most of V; Books VIII and IX are also
political); (ii) in relation to (i), a theory of knowledge (V VIII
and X). In this second division the Republic should be
taken in conjunction with the The&lelus ; it takes a positive
dogmatic attitude with regard to those points which the
latter treats in form of search. It is probable that this
(excepting Book X) is the only part of the Republic written
in the third period, showing Plato's theory as it does, in the
more developed stage.

The German line of thought tends to regard Plato as
a connected and consistent thinker. Grote, on the other
hand, finds him inconsistent with himself at different stages
of his philosophy. It is for us to distinguish him in his nega-
tive attitude (Thecctetus] and his positive attitude (Republic).



204 Elements of General Philosophy. [LECT.

It is in the philosophical part of the Republic that the latter,
viz. his dogmatic Idealism, is most fixed and characteristic,
though not yet in its final form. It undergoes further
development in the Parmenides, Sophistes, Philebus, and
Timceus, certain parts of the Republic theory being dropped,
others exclusively developed and emphasised, though nothing
is added.

Now the Thecetetus is obviously preparatory to a possible
solution of the question of the problem of knowledge
universally put, first in Phcedo and Republic, later in Par-
menides, Sophistes, Philebus, and Timceus, which four embody
the earlier solution in a modified form. It sweeps away
previous insufficient solutions as a preparation for one thafc.
shall be complete, while itself containing no direct statement
of his ideas. Is then the Thecetelus preparatory to the Republic
and Phcedo (ante B.C. 367), or to the remaining four
(post 360) ?

We must distinguish, in the dialogue, the essential from
the unessential. It has two episodes, very striking but not
related to the general argument, viz. an artistic description
of the Socratic method, and a comparison of the man of
the world with the philosopher. The brilliancy of these
episodes makes many call the dialogue an early work, the
later dialogues not containing writings of this kind, but this
does not prove much. However that may be, apart from these
episodes we get a consideration of three answers to the
question What is knowledge (Arurrijfwj) ? current in Plato's
day: (i) Knowledge is sense-perception; (2) Knowledge
is true opinion ; (3) Knowledge is true opinion, /iera Xo'you, i.e.
with a rational explanation or definition. All these views
had unquestionably found expression before Plato wrote,
though, except the first, not before Socrates lived. Plato



xx.] Elements of General Philosophy. 205

found them all insufficient. He first assigns (i) to Pro-
tagoras, then connects it with the Heracleitean doctrine of
perpetual flux. All the physicists, so far as they touched
on the problem of knowledge at all, gave the first answer.
It is doubtful whether it really coincided with all that
Protagoras meant when he put forward his doctrine of
homo mensura ; it remains the obvious answer of practical
every-day men.

Note in passing the remarkable affinity of Protagoras
and Hume. Both were Individualists and Relativists ; and
Protagoras anticipated many of Hume's sceptical results.
His treatise on Truth, from which Plato quotes, was pro-
bably not a developed consideration of the subject, or we
should have more of it in the Theatetus. Plato himself
developed the view of Protagoras, imputing to him a more
thorough-going notion of the relativity of sense than even
the latter held, and thus makes way for his own position.
By exaggerating the relativity of sense he throws us back
on something opposed to sense ; whereas modern philosophy
has shown that, even though sense as such is not knowledge,
there is no real knowledge apart from sense.

The third view of knowledge belongs in a sense to
Socrates and Plato themselves, fjara \6yov referring either
to the Socratic definition by enumeration of elements, or to
the earlier Platonic definition by characteristic difference.
The second view joins closely to the first and belongs to no
particular thinker. In explaining it Plato shows pyscho- .
logically that opinion is sense intelligently interpreted, i e.
is perception involving representation. (This he illustrates
by the metaphors of wax and the pigeons.) Here, while
he makes light of the view as answering his epistemo-
logical question, he shows great psychological insight, his



206 Elements of General Philosophy. [LECT.

explanation of perception being worthy of ranking beside
Hume's account of imagination.

The argument that knowledge is sensation, is disposed
of by Plato through the fact that knowledge is the activity of
the soul itself. If we see, it is through the soul's instrument.
The cognition of the soul, i.e. its powers of comparison, are
not attainable through sense. Sense is not even an element
of knowledge.

This last assertion is Plato's characteristic exaggeration,
and leads up to his theory that knowledge consists in merely
thinking of our ideas. How this position was taken up and
modified by modern Rationalist thought, how Locke and his
school vindicated sense, how for Condillac knowledge wa^
sense transformed, how Kant developed Leibniz's conception
of knowledge as arising from intellectual predispositions
into 'forms,' while requiring sense to furnish 'matter,' we
have already seen. Af.er all Plato may be said to have
adumbrated modern views, for he practically committed
himself to the doctrine that knowledge is an affair of mental
activity, the furnishing forth of certain ideas (KOIVU) on
occasion, and by comparison, of sensations.

Into his discussion of ' Knowledge is true opinion/ Plato
again insinuates much acute psychology, especially as to
the imagination that is present in perception (true opinion),
and distinguishes the latter from illusion (false opinion).
Opinion, for him, is intellectual representation of sense.
Note the grounds on which, namely, in the example of the
lawyer, he bases his rejection of this definition of knowledge :
the argument is another preparation for his theory of
ideas. True opinion rests on intelligent perception of sense
(answer 2 being resolved into answer i), and therefore, being
concerned with sense, is not knowledge. On his distinction



xx.] Elements of General Philosophy. 207

between opinion (Soa) and thinking (Sidfoin) he bases his
whole theory of ideas.

The third view breaks down because Xo'yor, in any of
its three senses, viz. description, induction of particulars,
division (bringing species under genus), is shown to be
involved in the meaning of opinion is a working with
sense, i. e. with particular experience relative to the individual
and is therefore no adequate expression of knowledge.
Hence answer (3) is resolved into answers (i) and (2). The
dialogue ends abruptly.

Plato's theory of knowledge in the Republic is set forth
in connexion with the education of the Guardian or philo-
sopher. Thus this epistemology is linked with his doctrine
of the state and the notion of virtue. Here (end of Book V)
he recognises knowledge and opinion as opposed. But
afterwards we find him opposing knowledge (having being
for its object) to ignorance (as related to the non-existent),
opinion coming midway (having as its object multiplex
experience). Later on, however (end of Book VI), igno-
rance is dropped from consideration. None of the diffi-
culties discussed in the The&tetus occur here ; they have either
vanished or not yet arisen, according to the date of the
latter. Plato dwells rather on multiplicity than on becoming,
distinguishing the Idea from its manifold manifestations. His

O O

great positive doctrine grew up in him in relation to the view
of Socrates, that knowledge is of the universal. Socrates
cared only for general ethical conceptions ; and he sought
to get at our concepts or universal notions, for purposes of
regulation, by means of analysis or definition. Plato applied
the Socratic analysis (explication, definition) of the ethical
notion to metaphysic. The object of knowledge, he
maintained, is more real than the object of opinion or of



208 Elements of General Philosophy. [LECT.

sense. The idea is what really is, though the object of
opinion is related to the idea. Nevertheless the ethical
conception is uppermost with Plato also. The idea of the
Good is the highest with which knowledge is conversant,
and is its ultimate end.

In the sixth book Plato works out the philosopher's
position in the world and the state. We may in this con-
nexion compare the first two-thirds of the book with the
episode of the philosopher and the man of the world in the
Thealetus, The strain is the same, although in the Republic
there is the additional and apparently inconsistent conception
that the philosopher, even if unpractical, ought to be ruler.
After this episode Plato again reverts to epistemology in a*
passage of great importance. Note how he dwells on the
idea of the Good as the highest with which knowledge is con-
versant, how it is related to other ideas, and finally the illus-
tration of the sun. Good is the ultimate end of knowledge,
the true aim of all real philosophy.

In the last pages of this book he advances beyond his
position, at the end of Book V, as to knowledge and opinion
(illustrated by the section of a line), in distinguishing between
the work of reason (vovs) and that of understanding (Sii/ota),
and between opinion as belief (ni<mi) and as conjecture
(ftVao-t'u), both belief and conjecture being concerned with
particulars, that is, with sense-experience. In both reason
and understanding we are occupied with ideas, with the
abstract, with knowledge, but in understanding we bring in
certain sensible manifestations, namely, in mathematics, the
highest of the special sciences, while in purely rational know-
ledge we are occupied with pure ideas (dialectic). Thus the
doctrine given in Book V is here expanded and developed.
But distinguish carefully the method of dialectic and the method



xx.] Elements of General Philosophy. 209

of dianoetic (special science). Plato is very modern here, and
it was he who originated the distinction between reason and
understanding. He practically marked out the whole sphere of
philosophy. In the seventh book he gives a most remarkable
classification of the sciences, which holds against some of the
present day \

Dialectic is rational conversance with ideas, is in fact philo-
sophy. As method Plato opposes it to that of the sciences,
taking mathematics as representing the latter. Mathematics,
he said, starts from hypotheses, working deductively by
synthetic combination, without going back to question the
fundamental data (axioms and definitions) whence it starts,
whereas the philosopher is concerned to inquire into these.
Philosophy is conversant with ideas as such; science, with
ideas as they may be sensibly represented.

Mathematics is often spoken of as the only differentiated
science in ancient time ; in Plato, however, a multiplicity
of sciences is mentioned. And note the order of study in
the sciences prescribed, after music and gymnastics, under the
system of training for a philosopher. The philosopher is to
be trained in the abstract consideration of sensible things, as
suggestive of reality beyond sense. Scientific considerations
should lead up to philosophy. Under the former the most
prominent is the numerical aspect of things. It was not till
Post-Platonic thought that arithmetic was subordinated to
geometry. Euclid, for exam pie. gives his arithmetical theory
of proportions (Books VI-IX) after treating (in Books I-IV)
of notions of space. But arithmetic is more general, and
Comte followed Plato in giving it priority as an abstract
science of wider application than geometry. Plato, again,

1 The simile of the cave in Book VII is an application of the end
of Book VI.



2io Elements of General Philosophy. [LECT.

saw that before we pass from the formal to the actual con-
sideration of things we must deal with solid geometry and
astronomy. Comte followed him here also, including physics.
Plato's statements show that physics was studied in his time,
but it was not till Galileo that its position was rightly
recognised.

In Book X of t^e Republic we have a statement of Plato's
theory of ideas (see ante, Lecture VIII). The meaning
attached by him to idea is not the more modern one of merely
' something before the mind,' but that of something objectively
real a meaning that comes out in the equivalent term ' form.'
Corresponding to any concept, which we form psychologically
by bringing together a multitude of particular experiences*
there is in the region of existence, of reality, a Form or Idea.
We get, for example, a concept of ' bad ' by comparison of
particular bad things, but there is a real Bad to which our
concept is related. Six different kinds of Ideas are put
forward in the Republic : (i) The supreme Idea, that of the
Good. Plato sought to establish a hierarchy of ideas, headed
by this one, but when he tries to fix the relation of the Good
to other ideas, he betrays uncertainty and incompleteness.
(2) Ideas of qualities akin to the Good, e.g. the just, the
honourable, &c. (3) Ideas of natural objects man, horse, &c.
(4) Ideas of artificial things, e. g. bed. (5) Ideas of relations,
such as equal, like, &c. (6) Ideas of qualities antagonistic
to the Good, e. g. unjust.

Such is the only way in which he could account for know-
ledge. In the Phado, where the epistemological position is
parallel to that in the Republic, he entered more closely into
the relation of the particular to the universal, of the particular
thing of sense to the pure foim or idea. Things of sense
have a reality, he found, only to the extent that they have



xx.] Elements of General Philosophy. 211

participation in (it4$*u) t or presence of (Trapovo-ia), the idea,
or communion (WMM*B) of the idea with the thing. And
because there are ultimate realities in which sensible things
participate, therefore knowledge is possible. From sense we
may mount up to the real, using especially mathematics as
an aid.

Aristotle, in his theorising concerning knowledge, which
occurs especially in the Melaphysica, criticises Plato's episte-
mology and sets up a counter-theory. Reality appeared to
him an ambiguous term, but lay rather in the concrete parti-
cular thing than in the universal or Platonic Idea, yet for him
too, although he allowed that the particular does really exist,
knowledge is of the universal only. Again, therefore, there
arises the question of the relation between universal and
particular, which he settled by his theory of essence.

Now Aristotle's criticisms referred to a later development of
Plato's theory than that given in the Republic, for according to
Aristotle the Ideas were of natural things, but not of artificial
things or relations. Already in this dialogue and the Phczdo,
Plato expresses dissatisfaction with his theory, and proceeds
in the Parmemdes, as well as in the Sophistes, Philelus, and
TimcEus, to criticise it, his criticism in the first-named being
more shrewd and trenchant than Aristotle's. We find him, for
instance, anticipating the lalter's objection of the ' third man.'
But his treatment here is negative only; the self-criticism is
not final, as Grote suggested ; yet he maintains that knowledge
is impossible without a theory of ideas as real existences. It
is in the Timaus that we find the ultimate expression of his
doctrine, propounded with more confidence and definiteness,
although in mythological form, than in any other dialogue, and
in a way intended to evade the objections raised in the
Parmemdes. Here all Ideas are discarded save ihose of the

r 2



212 Elements of General Philosophy. [LECT.

Good and of Natural Kinds, and it is a question whether
from these he does not exclude all that are not living things
(including plants). Again in opposing things that are to
things that are merely becoming, i. e. things of sense, he no
longer looks askance at the latter as in the Republic, but
attempts to show how, by positing the Ideas of the Good and
of Natural Kinds, we can account for things as we find them
for the coming into existence of the natural world. He gives
us in fact a cosmogony. He is eager no longer to get from
the things of sense to reality, but from the region of reality to
come down to an explanation of our actual experience. The
crude position taken up in the Republic has been transformed
into an absolute Idealism. The only thing that really is?
is mind Mind the Universal, and finite minds in relation to,
being the outcome of, the Universal Mind. Experience is the
mode in which particular minds can take in the ultimate
reality that is concentrated in the Universal Mind. Thus the
form of doctrine in the Tim&us is more mystical, more removed
from actual experience, and yet it is given to account for this
experience, and not as in the Republic to shun all explanation.
The Idea is no longer a reality apart ; ultimate reality is now
for him certain types of things in the universal mind, and
particular things are related to these types, not as participating
in them that theory has dropped out but as images or like-
nesses of a pattern, model or archetype (napdSfiyfjLa). They
are the way in which the finite mind of man represents to itself
the thought of the universal or divine mind. Only Hegel
reached a more extreme form of Idealism than this.

We see then that between the earlier position of the Republic
and the later one of the Timaus, the Thealeius is important
as indicating transition. The Parmenides is destructive ; the
Thea/etus points the way to reconstruction. With the final



xx.j Elements of General Philosophy. 213

view given in the Timoeus Plato never shows dissatisfaction.