THE SCEPTICS AND ECLECTICS: GREEK PHILOSOPHY IN ROME.
I.
The year 155 B.C. was signalised by an important event, if not in the
history of ideas, at least in the history of their diffusion. This
was the despatch of an embassy from the Athenian people to the Roman
Senate, consisting of three philosophers, the heads of their respective
schools—Carneades the Academician, Critolaus the Peripatetic,
and Diogenes the Stoic. Philosophic teaching, once proscribed at
Athens, had, at the time of which we are speaking, become her chief
distinction, and the most honourable profession pursued within her
precincts. It was, then, as natural that an important mission should be
confided to the most eminent representatives of the calling in question
as that high ecclesiastics should be similarly employed by Rome in
later ages, or that German university towns should send professors to
represent their interests in the imperial Diet. But the same fate that
befalls an established religion had befallen an established philosophy.
An attempt to impose restrictions on the liberty of teaching had,
indeed, been successfully resisted, and the experiment was never
repeated.[212] Nevertheless, the teachers themselves lost as much in
true dignity as they gained in affluence and popular estimation. In all
probability, the threat of death would not have induced Socrates to
undertake the task which was, apparently, accepted without compulsion
and as an honourable duty by his successors. The Athenians had made an
unprovoked raid on the town of Oropus; the affair had been referred to
arbitration; and the aggressors had been sentenced to pay a fine of 500
talents. It was to obtain a remission of this sentence that the three
Scholarchs were sent on an embassy to the Roman Senate.
If the nature of their errand was not precisely calculated to win
respect for the profession of the Athenian envoys, the subsequent
proceedings of one among their number proved still less likely to raise
it in the estimation of those whose favour they sought to win. Hellenic
culture was, at that time, rapidly gaining ground among the Roman
aristocracy; Carneades, who already enjoyed an immense reputation for
eloquence and ingenuity among his own countrymen, used the opportunity
offered by his temporary residence in the imperial city to deliver
public lectures on morality; and such was the eagerness to listen that
for a time the young nobles could think and talk of nothing else. The
subject chosen was justice. The first lecture recapitulated whatever
had been said in praise of that virtue by Plato and Aristotle. But
it was a principle of the sect to which Carneades belonged that
every affirmative proposition, however strongly supported, might be
denied with equal plausibility. Accordingly, his second discourse
was entirely devoted to upsetting the conclusions advocated in the
first. Transporting the whole question, as would seem, from a private
to a public point of view, he attempted to show, from the different
standards prevailing in different countries, that there was no such
thing as an immutable rule of right; and also that the greatest and
most successful States had profited most by unscrupulous aggressions
on their weaker neighbours—his most telling illustrations being drawn
from the history of the Romans themselves. Then, descending once more
to private life, the sceptical lecturer expatiated on the frequency
of those cases in which justice is opposed to self-interest, and the
folly of sacrificing one’s own advantage to that of another. ‘Suppose
a good man has a runaway slave or an unhealthy house to sell, will
he inform the buyer of their deficiencies, or will he conceal them?
In the one case he will be a fool, in the other case he will be
unjust. Again, justice forbids us to take away the life or property
of another. But in a shipwreck, will not the just man try to save his
life at another’s expense by seizing the plank of which some weaker
person than himself has got hold—especially if they are alone on the
sea together? If he is wise he will do so, for to act otherwise would
be to sacrifice his life. So also, in flying before the enemy, will
he not dispossess a wounded comrade of his horse, in order to mount
and escape on it himself? Here, again, justice is incompatible with
self-preservation—that is to say, with wisdom!‘[213]
At the time when Carneades delivered his lectures, the morality of
Rome resembled that of Sparta during her great conflict with Athens,
as characterised by one of the speakers in the Melian Dialogue.
Scrupulously honourable in their dealings with one another, in their
dealings with foreign nations her citizens notoriously identified
justice with what was agreeable or advantageous to themselves. The
arguments of the Academic philosopher must, therefore, have been
doubly annoying to the leaders of the State, as a satire on its public
policy and as a source of danger to the integrity of its private
life. In this respect, old Cato was a type of the whole race. In all
transactions with his fellow-citizens, and in every office undertaken
on behalf of the community, his honesty was such that it became
proverbial. But his absolute disregard of international justice has
become equally proverbial through the famous advice, reiterated on
every possible occasion, that an unoffending and unwarlike city should
be destroyed, lest its existence should at some future time become a
source of uneasiness to the mistress of the world. Perhaps it was a
secret consciousness of his own inconsistency which prevented him from
directly proposing that Carneades should not be allowed to continue
his lectures. At any rate, the ex-Censor contented himself with moving
that the business on which the Athenian envoys had come should be at
once concluded, that they might return to their classes at Athens,
leaving the youth of Rome to seek instruction as before from the wise
conversation and example of her public men.[214] We are not told
whether his speech on this occasion wound up with the usual formula,
_caeterum, Patres Conscripti, sententia mea est Carthaginem esse
delendam_; but as it is stated that from the year 175 to the end of
his life, he never made a motion in the Senate that was not terminated
by those words, we are entitled to assume that he did not omit them
in the present instance. If so, the effect must have been singularly
grotesque; although, perhaps, less so than if attention had been
drawn to the customary phrase by its unexpected absence. At any rate,
Carneades had an opportunity of carrying back one more illustration of
ethical inconsistency wherewith to enliven his lectures on the ‘vanity
of dogmatising’ and the absolute equilibrium of contradictory opinions.
It has been mentioned that Carneades was the head of the Academic
school. In that capacity, he was the lineal inheritor of Plato’s
teaching. Yet a public apology for injustice, even when balanced by a
previous panegyric on its opposite, might seem to be of all lessons the
most alien from Platonism; and in a State governed by Plato’s own laws,
it would certainly have been punishable with death. To explain this
anomaly is to relate the history of Greek scepticism, which is what we
shall now attempt to do.
II.
In modern parlance, the word scepticism is often used to denote
absolute unbelief. This, however, is a misapplication; and, properly
speaking, it should be reserved, as it was by the Greeks, for those
cases in which belief is simply withheld, or in which, as its etymology
implies, the mental state connoted is a desire to consider of the
matter before coming to a decision. But, of course, there are occasions
when, either from prudence or politeness, absolute rejection of a
proposition is veiled under the appearance of simple indecision or
of a demand for further evidence; and at a time when to believe in
certain theological dogmas was either dangerous or discreditable,
the name sceptic may have been accepted on all hands as a convenient
euphemism in speaking about persons who did not doubt, but denied
them altogether. Again, taken in its original sense, the name sceptic
is applicable to two entirely different, or rather diametrically
opposite classes. The true philosopher is more slow to believe than
other men, because he is better acquainted than they are with the
rules of evidence, and with the apparently strong claims on our belief
often possessed by propositions known to be false. To that extent,
all philosophers are sceptics, and are rightly regarded as such by
the vulgar; although their acceptance of many conclusions which the
unlearned reject without examination, has the contrary effect of giving
them a reputation for extraordinary credulity or even insanity. And
this leads us to another aspect of scepticism—an aspect under which,
so far from being an element of philosophy, it is one of the most
dangerous enemies that philosophy has to face. Instead of regarding
the difficulties which beset the path of enquiry as a warning against
premature conclusions, and a stimulus to more careful research, it is
possible to make them a pretext for abandoning enquiry altogether. And
it is also possible to regard the divergent answers given by different
thinkers to the same problem, not as materials for comparison,
selection or combination, nor even as indications of the various
directions in which a solution is not to be sought, but as a proof
that the problem altogether passes the power of human reason to solve.
Were this intellectual despondency to issue in a permanent suspense of
judgment, it would be bad enough; but practically its consequences are
of a much more mischievous character. The human mind is so constituted
that it must either go forward or fall back; in no case can it stand
still. Accordingly, the lazy sceptic almost always ends by conforming
to the established creeds and customs of his age or of the society
in which he lives; thus strengthening the hands of authority in its
conflict with the more energetic or courageous enquirers, whose object
is to discover, by the unaided efforts of reason, some new and positive
principle either of action or of belief. And the guardians of orthodoxy
are so well aware of the profit to be reaped from this alliance that,
when debarred from putting down their opponents by law or by public
opinion, they anxiously foster false scepticism where it is already
rampant, and endeavour to create it where it does not exist. Sometimes
disinterested morality is the object of their attack, and at other
times the foundations of inductive science. Their favourite formula
is that whatever objections may be urged against their own doctrines,
others equally strong may be urged against the results of free thought;
whereas the truth is that such objections, being applicable to all
systems alike, exactly balance one another, leaving the special
arguments against irrationalism to tell with as much force as before.
And they also lay great stress on the internal dissensions of their
assailants—dissensions which only bring out into more vivid relief the
one point on which all are agreed, that, whatever else may be true, the
traditional opinions are demonstrably false.
As might be expected from the immense exuberance of their intellectual
life, we find every kind of scepticism represented among the
Greeks; and, as with their other philosophical tendencies, there is
evidence of its existence previous to or independent of scientific
speculation. Their very religion, though burdened with an enormous mass
of fictitious legends, shows a certain unwillingness to transgress
the more obvious laws of nature, not noticeable in the traditions
of kindred or neighbouring races. Its tendency is rather to imagine
supernatural causes for natural events, or to read a divine meaning
into accidental occurrences, than to introduce impossibilities into the
ordinary course of history. And some of its most marvellous stories
are told in such a manner that the incredulous satire with which they
were originally received is, by a beautiful play of irony, worked into
the very texture of the narrative itself. For example, the Greeks
were especially disinclined to believe that one of the lower animals
could speak with a human voice, or that a dead man could be brought
back to life—contradicted as both suppositions were by the facts of
universal experience. So when the horse Xanthus replies to his master’s
reproaches, Homer adds that his voice was arrested by the Erinyes—that
is to say, by the laws of nature; and we may suspect that nothing more
is intended by his speech than the interpretation which Achilles would
spontaneously put on the mute and pathetic gaze of the faithful steed.
And when, to illustrate the wondrous medical skill of Asclêpius, it is
related that at last he succeeded in restoring a dead man to life, the
story adds that for this impious deed both the healer and his patient
were immediately transfixed by a thunderbolt from heaven.[215] Another
impossibility is to predict with any certainty the future fate of
individuals, and here also—as has been already observed in a different
connexion[216]—the Greeks showed their extreme scepticism with regard
to any alleged contravention of a natural law, under the transparent
disguise of stories about persons whom ambiguous predictions had lured
to their fall.
It is even doubtful how far the Greek poets believed in the personality
of their gods, or, what comes to the same thing, in their detachment
from the natural objects in which a divine power was supposed to be
embodied. Such a detachment is most completely realised when they are
assembled in an Olympian council; but, as Hegel has somewhere observed,
Homer never brings his gods together in this manner without presenting
them in a ridiculous light—that is to say, without hinting that their
existence must not be taken quite in earnest. And the existence of
disembodied spirits seems to be similarly conceived by the great epic
master. The life of the souls in Hades is not a continuance but a
memory and a reflection of their life on earth. The scornful reply
of Achilles to the congratulations of Odysseus implies, as it were,
the consciousness of his own nonentity. By no other device could the
irony of the whole situation, the worthlessness of a merely subjective
immortality, be made so poignantly apparent.[217]
The characters in Homer are marked by this incredulous disposition in
direct proportion to their general wisdom. When Agamemnon relates his
dream to the assembled chiefs, Nestor dryly observes that if anyone of
less authority had told them such a story they would have immediately
rejected it as untrue. Hector’s outspoken contempt for augury is well
known; and his indifference to the dying words of Patroclus is equally
characteristic. In the _Odyssey_, Alcinous pointedly distinguishes his
guest from the common run of travellers, whose words deserve no credit.
That Telemachus should tell who is his father, with the uncomplimentary
reservation that he has only his mother’s word for it, is evidently
meant as a proof of the young man’s precocious shrewdness; and it is
with the utmost difficulty that Penelope herself is persuaded of her
husband’s identity. So in the _Agamemnon_ of Aeschylus, nothing less
than the report of an eye-witness will convince the Chorus of old men
that Troy has really fallen.[218] Finally, to complete the list of
examples afforded independently of philosophical reflection, Herodotus
repeatedly expresses disbelief in the stories told him, or, what is
more remarkable, holds his judgment in suspense with regard to their
veracity.
Scepticism, as a philosophical principle, is alien from early Greek
thought; but it is pervaded by a negative tendency exhibited in four
different directions, all converging towards the later attitude of
suspensive doubt. There are sharp criticisms on the popular mythology;
there are protests against the ascription of reality to sensible
appearances; there are contemptuous references on the part of some
philosophers to the opinions held by others; and there are occasional
lamentations over the difficulty of getting at any truth at all. The
importance, however, of these last utterances has been considerably
exaggerated both in ancient and modern times. For, in some instances,
they are attributable solely to the distrust of sense-perception, and
in others they seem to express nothing more than a passing mood against
which we must set the dogmatic conclusions elsewhere enunciated with
perfect confidence by the same thinkers.[219] At the same time, we
have to note, as an illustration of the standing connexion between
theological belief and that kind of scepticism which is shown by
distrust in man’s power of discovering the truth for himself, that the
strongest expressions of such a distrust are to be found in the two
most religious of the pre-Socratic thinkers, Xenophanes and Empedocles.
III.
A new period begins with the Greek Humanists. We use this term in
preference to that of Sophists, because, as has been shown, in
specially dealing with the subject, half the teachers known under the
latter denomination made it their business to popularise physical
science and to apply it to morality, while the other half struck out
an entirely different line, and founded their educational system on
the express rejection of such investigations; their method being,
in this respect, foreshadowed by the greatest poet of the age, who
concentrates all his attention on the workings of the human mind, and
followed by its greatest historian, with whom a similar study takes
the place occupied by geography and natural history in the work of
Herodotus. This absorption in human interests was unfavourable alike
to the objects and to the methods of previous enquiry: to the former,
as a diversion from the new studies; to the latter, as inconsistent
with the flexibility and many-sidedness of conscious mind. Hence the
true father of philosophical scepticism was Protagoras. With him, for
the first time, we find full expression given to the proper sceptical
attitude, which is one of suspense and indifference as opposed to
absolute denial. He does not undertake to say whether the gods exist or
not. He regards the real essence of Nature as unknowable, on account
of the relativity which characterises all sensible impressions. And
wherever opinions are divided, he undertakes to provide equally strong
arguments for both sides of the question. He also anticipates the two
principal tendencies exhibited by all future scepticism in its relation
to practice. One is its devotion to humanity, under the double form
of exclusive attention to human interests, and great mildness in the
treatment of human beings. The other is a disposition to take custom
and public opinion, rather than any physical or metaphysical law, for
the standard and sanction of morality. Such scepticism might for the
moment be hostile to religion; but a reconciliation was likely to be
soon effected between them.
The famous theses of Gorgias were quoted in a former chapter as
an illustration of the tactics pursued by Greek Humanism in its
controversy with physical science. They must be noticed again in the
present connexion, on account of their bearing on the development of
scepticism, and as having inaugurated a method of reasoning often
employed in subsequent attacks, directed, not against the whole of
knowledge, but against particular parts of it. The scepticism of
Protagoras rested on the assumption that there is an external reality
from the reaction of which with mind all our perceptions proceed.
Neither of these two factors can be known apart from the other,
and as both are in a constant flux, our knowledge of the resulting
compound at one time does not show what it has been or will be at
another time. But Gorgias altogether denied the existence of any
objective reality; and he attempted to disprove it by an analytical
instead of a synthetic argument, laying down a series of disjunctive
propositions, and upsetting the different alternatives in succession.
Existence must be either something or nothing, or both together; and if
something, it must be either finite or infinite, or both, and either
one or many, or both. His argument against an infinite existence is
altogether futile; but it serves to illustrate the undeveloped state
of reflection at that period. The eternity of the world is confounded
with its unlimited extension in space: and this hypothesis, again, is
met by the transparent quibble that the world, not being in any one
place, must be nowhere or not at all. And the alternative that the
world has not always existed is refuted by the unproved assumption,
which, apparently, no Greek philosopher ever thought of disputing,
that nothing can begin without being caused by something else. Still,
however contemptible such reasonings may seem, it is obvious that
in them we have the first crude form of the famous antinomies by
which Kant long afterwards sought to prove the impossibility of a
world existing in space and time apart from a percipient subject, and
which have since been used to establish in a more general way the
unknowability of existence as such. It will also be observed that the
sceptical arguments respectively derived from the relativity of thought
and from the contradictions inherent in its ultimate products are run
together by modern agnostics. But no reason that we can remember has
ever been given to show that an idea is necessarily subjective because
it is self-contradictory.
The second thesis of Gorgias was that, even granting the world
to exist, it could not possibly be known. Here the reasoning is
unexpectedly weak. Because all thoughts do not represent facts,—as,
for example, our ideas of impossible combinations, like chariots
running over the sea,—it is assumed that none do. But the problem how
to distinguish between true and false ideas was raised, and it was
round this that the fiercest battle between dogmatists and sceptics
subsequently raged. And in the complete convertibility of consciousness
and reality postulated by Gorgias, we may find the suggestion of a
point sometimes overlooked in the automatist controversy—namely,
that the impossibility, if any, of our acting on the material world
reciprocally involves the impossibility of its acting on us, in so
far as we are conscious beings. If thought cannot be translated into
movement, neither can movement be translated into thought.
The third thesis maintains that, granting the world to exist and to
be knowable, one man cannot communicate his knowledge to another;
for, the different classes of sensations being heterogeneous, a
visual or tactual impression on our consciousness cannot be conveyed
by an auditory impression on the consciousness of someone else. This
difficulty has been completely overcome by the subsequent progress of
thought. We cannot, it is true, directly communicate more than a few
sensations to one another; but by producing one we may call up others
with which it has become associated through previous experience. And
the great bulk of our knowledge has been analysed into relations of
co-existence, succession, and resemblance, which are quite independent
of the particular symbols employed to transmit them from one mind to
another.[220]
The scepticism of Aristippus and the Cyrenaics mediated between the
views of Protagoras and those of Gorgias, while marking an advance
on both. According to this school, we know nothing beyond our own
feelings, and it must be left undecided whether they are caused by
an external reality or not. Nor can the feelings of one individual
justify us in reasoning to the existence of similar feelings in
the mind of another individual.[221] It might be objected that the
arguments advanced in support of the latter assertion are suicidal,
for they are derived from the abnormal states of consciousness
accompanying particular diseases, or else from the divergences of
taste exhibited by different individuals even when in good health,—an
apparent admission that we are sufficiently well acquainted with the
phenomena in question to institute a comparison between them, which,
by hypothesis, is impossible. And this is, in fact, the method by
which Mr. Herbert Spencer has endeavoured to upset the whole theory
of subjective idealism, as involving at every step an assumption of
the very realities that it professes to deny. But the Cyrenaic and
the modern idealist have a perfect right to show that the assumptions
of their adversaries are self-contradictory; and the readiest way
of so doing is to reason from them as if they were true. The real
answer to that extreme form of idealism which denies the possibility
of making known our feelings to each other is that, our bodies being
similarly constructed and responding to similar impressions by similar
manifestations, I have the same sort of warrant for assuming that your
states of consciousness are like mine that I have for assuming you to
exist at all. The inference must, of course, be surrounded by proper
precautions, such as are seldom used by unscientific reasoners. We must
make sure that the structure is the same and that the excitement is the
same, or that their differences, if any, are insignificant, before we
can attribute the same value to the same manifestations of feeling on
the part of different persons; but that this can be done, at least in
the case of the elementary sensations, is shown by the easy detection
of such anomalies as colour-blindness where they exist.
With Socrates and Plato, scepticism exhibits itself under two new
aspects: as an accompaniment of religious belief, and as an element
of constructive thought. Thus they represent both the good and the
bad side of this tendency: the aspect under which it is a help, and
the aspect under which it is a hindrance to scientific investigation.
With both philosophers, however, the restriction or negation of human
knowledge was a consequence rather than a cause of their theological
convictions; nor do they seem to have appreciated its value as a weapon
in the controversy with religious unbelief. When Socrates represented
the irreconcilable divergence in the explanations of Nature offered
by previous thinkers as a sufficient condemnation of their several
pretensions, he did not set this fact against the arguments by which
a Xenophanes had similarly endeavoured to overthrow the popular
mythology; but he looked on it as a fatal consequence of their insane
presumption in meddling with the secrets of the gods. On one occasion
only, when explaining to Euthydêmus that the invisibility of the gods
is no reason for doubting their existence, he argues, somewhat in
Butler’s style, that our own minds, whose existence we cannot doubt,
are equally invisible.[222] And the Platonic Socrates makes it his
business to demonstrate the universality of human ignorance, not as a
caution against dogmatic unbelief, but as a glorification of the divine
knowledge; though how we come to know that there is any such knowledge
he leaves utterly unexplained.
In Plato’s _Parmenides_ we have to note the germ of a new dialectic.
There it is suggested that we may overcome the difficulties attending a
particular theory—in this instance the theory of self-existing ideas—by
considering how much greater are the difficulties which would ensue
on its rejection. The arguments advanced by Zeno the Eleatic against
the reality of motion are mentioned as a case in point; and Plato
proceeds to illustrate his proposed method by showing what consequences
respectively follow if we first assume the existence, and then the
non-existence of the One; but the whole analysis seems valueless for
its immediate purpose, since the resulting impossibilities on either
side are left exactly balanced; and Plato does not, like some modern
metaphysicians, call in our affections to decide the controversy.
The method by which Plato eventually found his way out of the sceptical
difficulty, was to transform it from a subjective law of thought
into an objective law of things. Adopting the Heracleitean physics
as a sufficient explanation of the material world, he conceived,
at a comparatively early period of his mental evolution, that the
fallaciousness of sense-impressions is due, not to the senses
themselves, but to the instability of the phenomena with which they
deal; and afterwards, on discovering that the interpretation of ideal
relations was subject to similar perplexities, he assumed that, in
their case also, the contradiction arises from a combination of Being
with not-Being determining whatever differences prevail among the
ultimate elements of things. And, finally, like Empedocles, he solved
the problem of cognition by establishing a parallel between the human
soul and the universe as a whole; the circles of the Same and the
Other being united in the celestial orbits and also in the mechanism
of the brain.[223]
It was by an analogous, though, of course, far more complicated and
ingenious adjustment, that Hegel sought to overcome the agnosticism
which Kant professed to have founded on a basis of irrefragable
proof. With both philosophers, however, the sceptical principle was
celebrating its supreme triumph at the moment of its fancied overthrow.
The dogmatism of doubt could go no further than to resolve the whole
chain of existence into a succession of mutually contradictory ideas.
If the synthesis of affirmation and negation cannot profitably be
used to explain the origin of things in themselves, it has a real and
very important function when limited to the subjective sphere, to the
philosophy of practice and of belief. It was so employed by Socrates,
and, on a much greater scale, by Plato himself. To consider every
proposition from opposite points of view, and to challenge the claim of
every existing custom on our respect, was a proceeding first instituted
by the master, and carried out by the disciple in a manner which has
made his investigations a model for every future enquirer. Something
of their spirit was inherited by Aristotle; but, except in his
logical treatises, it was overborne by the demands of a pre-eminently
dogmatic and systematising genius. In criticising the theories of his
predecessors, he has abundantly illustrated the power of dialectic,
and he has enumerated its resources with conscientious completeness;
but he has not verified his own conclusions by subjecting them to this
formidable testing apparatus.
Meanwhile the scepticism of Protagoras had not been entirely absorbed
into the systems of his rivals, but continued to exist as an
independent tradition, or in association with a simpler philosophy.
The famous school of Megara, about which, unfortunately, we have
received very little direct information, was nominally a development
of the Socratic teaching on its logical side, as the Cynic and
Cyrenaic schools were on its ethical side, but like them also, it
seems to have a more real connexion with the great impulse previously
given to speculation by the Sophists. At any rate, we chiefly hear
of the Megarians as having denied the possibility of definition, to
which Socrates attached so much importance, and as framing questions
not susceptible of a categorical answer,—an evident satire on the
Socratic method of eliciting the truth by cross-examination.[224]
What they really derived from Socrates seems to have been his mental
concentration and independence of external circumstances. Here they
closely resembled the Cynics, as also in their contempt for formal
logic; but while Antisthenes found a sanction for his indifference
and impassivity in the order of nature, their chief representative,
Stilpo, achieved the same result by pushing the sceptical principle
to consequences from which even the Cyrenaics would have shrunk.
Denying the possibility of attaching a predicate to a subject, he
seems, in like manner, to have isolated the mind from what are called
its affections, or, at least, to have made this isolation his ideal
of the good. Even the Stoics did not go to such a length; and Seneca
distinguishes himself from the followers of Stilpo by saying, ‘Our sage
feels trouble while he overcomes it, whereas theirs does not feel it at
all.’[225]
IV.
So far, the sceptical theory had been put forward after a somewhat
fragmentary fashion, and in strict dependence on the previous
development of dogmatic philosophy. With the Humanists it had taken
the form of an attack on physical science; with the Megarians, of a
criticism on the Socratic dialectic; with both, it had been pushed
to the length of an absolute negation, logically not more defensible
than the affirmations to which it was opposed. What remained was that,
after being consistently formulated, its results should be exhibited
in their systematic bearing on the practical interests of mankind. The
twofold task was accomplished by Pyrrho, whose name has accordingly
continued to be associated, even in modern times, with the profession
of universal doubt. This remarkable man was a native of Elis, where a
branch of the Megarian school had at one time established itself; and
it seems likely that the determining impulse of his life was, directly
or indirectly, derived from Stilpo’s teaching. A contemporary of
Alexander the Great, he accompanied the Macedonian army on its march to
India, subsequently returning to his native city, where he died at an
advanced age, about 275 B.C. The absurd stories about his indifference
to material obstacles when out walking have been already mentioned in a
former chapter, and are sufficiently refuted by the circumstances just
related. The citizens of Elis are said to have shown their respect for
the philosopher by exempting him from taxation, appointing him their
chief priest—no inappropriate office for a sceptic of the true type—and
honouring his memory with a statue, which was still pointed out to
sightseers in the time of Pausanias.[226]
Pyrrho, who probably no more believed in books than in anything else,
never committed his opinions to writing; and what we know of them is
derived from the reports of his disciples, which, again, are only
preserved in a very incomplete form by the compilers of the empire.
According to these, Pyrrho began by declaring that the philosophic
problem might be summed up in the three following questions: ‘What
is the nature of things? What should be our relation to them? What is
the practical consequence of this determination?’ Of its kind, this
statement is probably the best ever framed, and might be accepted
with equal readiness by every school of thought. But the scepticism
of Pyrrho at once reveals itself in his answer to the first question.
We know nothing about things in themselves. Every assertion made
respecting them is liable to be contradicted, and neither of the two
opposing propositions deserves more credence than the other. The
considerations by which Pyrrho attempts to establish this proposition
were probably suggested by the systems of Plato and Aristotle. The
only possible avenues of communication with the external world are,
he tells us, sense and reason. Of these the former was so universally
discredited that he seems to have regarded any elaborate refutation
of its claims as superfluous. What we perceive by our senses is the
appearance, not the reality of things. This is exactly what the
Cyrenaics had already maintained. The inadequacy of reason is proved
by a more original method. Had men any settled principles of judgment,
they would agree on questions of conduct, for it is with regard to
these that they are best informed, whereas the great variety of laws
and customs shows that the exact opposite is true. They are more
hopelessly divided on points of morality than on any other.[227] It
will be remembered that Pyrrho’s fellow-townsman, Hippias, had, about
a hundred years earlier, founded his theory of Natural Law on the
arbitrary and variable character of custom. The result of combining
his principles with those professed by Protagoras and Gorgias was to
establish complete moral scepticism; but it would be a mistake to
suppose that moral distinctions had no value for him personally, or
that they were neglected in his public teaching.
Timon, a celebrated disciple of Pyrrho, added another and, from the
speculative point of view, a much more powerful argument, which,
however, may equally have been borrowed from the master’s lectures.
Readers of the _Posterior Analytics_ will remember how strongly
Aristotle dwells on the necessity of starting with first principles
which are self-evidently true. The chain of demonstration must have
something to hang on, it cannot be carried back _ad infinitum_. Now,
Timon would not admit of such a thing as first principles. Every
assumption, he says, must rest on some previous assumption, and as this
process cannot be continued for ever, there can be no demonstration
at all. This became a very favourite weapon with the later Sceptics,
and, still at the suggestion of Aristotle, they added the further
‘trope’ of compelling their adversaries to choose between going back
_ad infinitum_ and reasoning in a circle—in other words, proving the
premises by means of the conclusion. Modern science would not feel much
appalled by the sceptical dilemma. Its actual first principles are
only provisionally assumed as ultimate, and it is impossible for us
to tell how much farther their analysis may be pursued; while, again,
their validity is guaranteed by the circular process of showing that
the consequences deduced from them agree with the facts of experience.
But as against those modern philosophers who, in adherence to the
Aristotelian tradition, still seek to base their systems on first
principles independent of any individual experience, the sceptical
argument is unanswerable, and has even been strengthened by the
progress of knowledge. To this day, thinkers of different schools
cannot agree about the foundations of belief, and what to one seems
self-evidently true, is to another either conceivably or actually
false. To Mr. Herbert Spencer the persistence of force is a necessary
truth; to Prof. Stanley Jevons its creation is a perfectly possible
contingency; while to others, again, the whole conception of force, as
understood by Mr. Spencer, is so absolutely unmeaning that they would
decline to entertain any proposition about the invariability of the
objective reality which it is supposed to represent. And when the _à
priori_ dogmatist affects to treat the negations of his opponents as
something that they do not think, but only think they think, they may,
with perfect fairness, attribute his rejection of their beliefs—as,
for example, free-will—to a similar subjective illusion. Moreover, the
pure experimentalists can point to a circumstance not foreseen by the
ancient sceptics, which is that propositions once generally regarded
as incontrovertible by thinking men, are now as generally abandoned by
them.
Having proved, to his satisfaction, that the nature of things is
unknowable, Pyrrho proceeds to deal with the two remaining heads of the
philosophic problem. To the question what should be our relation to a
universe which we cannot reach, the answer is, naturally, one of total
indifference. And the advantage to be derived from this attitude is, he
tells us, that we shall secure the complete imperturbability wherein
true happiness consists. The sceptical philosophy does not agree with
Stilpo in denying the reality of actual and immediate annoyances, for
it denies nothing; but it professes to dispel that very large amount
of unhappiness which arises from the pursuit of fancied goods and the
expectation of future calamities. In respect to the latter, what Pyrrho
sought was to arrive by the exercise of reasoning at the tranquillity
which unreasoning animals naturally enjoy. Thus, we are told that,
when out at sea in a storm, he called the attention of the terrified
passengers to a little pig which was quietly feeding in spite of the
danger, and taught them that the wise man should attain to a similar
kind of composure.
Various other anecdotes of more or less doubtful authenticity are
related, showing that the philosopher could generally, though not
always, act up to his own ideal of indifference. He lived with his
sister, who was a midwife by profession, and patiently submitted to the
household drudgery which she unsparingly imposed on him. Once, however,
she succeeded in goading him into a passion; and on being rather
inopportunely reminded of his professed principles by a bystander,
the sceptic tartly replied that a wretched woman like that was no
fit subject for a display of philosophical indifference. On another
occasion, when taunted for losing his self-possession at the attack of
a furious dog, he observed, with truth, that, after all, philosophers
are human beings.[228]
Thus we find Pyrrho competing with the dogmatists as a practical
moralist, and offering to secure the inward tranquillity at which
they too aimed by an easier method than theirs. The last eminent
representative of the sceptical school, Sextus Empiricus, illustrates
its pretensions in this respect by the well-known story of Apelles,
who, after vainly endeavouring to paint the foam on a horse’s mouth,
took the sponge which he used to wipe his easel, and threw it at
the picture in vexation. The mixture of colours thus accidentally
applied produced the exact effect which he desired, but at which no
calculation could arrive. In like manner, says Sextus, the confusion
of universal doubt accidentally resulted in the imperturbability which
accompanies suspense of judgment as surely as a body is followed by
its shadow.[229] There was, however, no accident about the matter at
all. The abandonment of those studies which related to the external
world was a consequence of the ever-increasing attention paid to
human interests, and that these could be best consulted by complete
detachment from outward circumstances, was a conclusion inevitably
suggested by the negative or antithetical moment of Greek thought.
Hence, while the individualistic and apathetic tendencies of the age
were shared by every philosophical school, they had a closer logical
connexion with the idealistic than with the naturalistic method;
and so it is among the successors of Protagoras that we find them
developed with the greatest distinctness; while their incorporation
with Stoicism imposed a self-contradictory strain on that system
which it never succeeded in shaking off. Epicureanism occupied a
position midway between the two extremes; and from this point of view,
we shall be better able to understand both its inherent weakness as
compared with the other ancient philosophies, and the admiration which
it has attracted from opposite quarters in recent years. To some
it is most interesting as a revelation of law in Nature, to others
as a message of deliverance to man—not merely a deliverance from
ignorance and passion, such as its rivals had promised, but from all
established systems, whether religious, political, or scientific. And
unquestionably Epicurus did endeavour to combine both points of view
in his theory of life. In seeking to base morality on a knowledge of
natural law he resembles the Stoics. In his attacks on fatalism, in
his refusal to be bound down by a rigorously scientific explanation of
phenomena, in his failure to recognise the unity and power of Nature,
and in his preference of sense to reason, he partially reproduces the
negative side of Scepticism; in his identification of happiness with
the tranquil and imperturbable self-possession of mind, in his mild
humanism, and in his compliance with the established religion of the
land, he entirely reproduces its positive ethical teaching. On the
other hand, the two sides of his philosophy, so far from completing,
interfere with and mar one another. Emancipation from the outward world
would have been far more effectually obtained by a total rejection of
physical science than by the construction of a theory whose details
were, on any scientific principles, demonstrably untrue. The appeal
to natural instinct as an argument for hedonism would, consistently
followed out, have led to one of two conclusions, either of which is
incompatible with the principle that imperturbability is the highest
good. If natural instinct, as manifested by brutes, by children, and
by savages, be the one sure guide of action, then Callicles was right,
and the habitual indulgence of passion is wiser than its systematic
restraint. But if Nature is to be studied on a more specific and
discriminating plan, if there are human as distinguished from merely
animal impulses, and if the higher development of these should be our
rule of life, then Plato and Aristotle and the Stoics were right, and
the rational faculties should be cultivated for their own sake, not
because of the immunity from superstitious terrors which they secure.
And we may add that the attendance on public worship practised by
Epicurus agreed much better with the sceptical suspense of judgment
touching divine providence than with its absolute negation, whether
accompanied or not by a belief in gods who are indifferent to sacrifice
and prayer.
It was, no doubt, for these and similar reasons that all the most
vigorous intellects of Hellas ranged themselves either on the Stoic or
on the Sceptic side, leaving the halfhearted compromise of Epicurus
to those who could not think out any one theory consistently, or who,
like the Romans at first, were not acquainted with any system but his.
Henceforth, during a period of some centuries, the whole philosophic
movement is determined by the interaction of these two fundamental
forces. The first effect of their conflict was to impose on Scepticism
an important modification, illustrating its essentially parasitic
character. We have seen it, as a general tendency of the Greek mind,
clinging to the very texture of mythology, accompanying the earliest
systematic compilation of facts, aiding the humanistic attacks on
physical science, associated with the first great religious reaction,
operating as the dialectic of dialectic itself, and finally assuming
the form of a shadowy morality, in rivalry with and imitation of
ethical systems based on a positive and substantial doctrine. We have
now to trace its metamorphosis into a critical system extending its
ramifications in parallelism with the immense dogmatic structure of
Stoicism, and simultaneously endeavouring to reach the same practical
results by a more elastic adaptation to the infirmities of human
reason and the uncertainties of sensible experience. As such, we
shall also have to study its influence over the most plastic of Roman
intellects, the great orator in whose writings Greek philosophy was
reclothed with something of its ancient charm, so that many who were
debarred from admission to the groves and porticoes of Athens have
caught an echo of the high debates which once stirred their recesses,
as they trod the shady slopes of Tusculum under his visionary guidance,
or followed his searching eyes over the blue waters to Pompeii, while
he reasoned on mind and its object, on sense and knowledge, on doubt
and certainty, with Lucullus and Hortensius, on the sunlight Baian
shore. It is the history of the New Academy that we shall now proceed
to trace.
V.
When we last had occasion to speak of the Platonic school, it was
represented by Polemo, one of the teachers from whose lessons Zeno the
Stoic seems to have compiled his system. Under his superintendence,
Platonism had completely abandoned the metaphysical traditions of
its founder. Physics and dialectics had already been absorbed by
Aristotelianism. Mathematics had passed into the hands of experts.
Nothing remained but the theory of ethics; and, as an ethical teacher,
Polemo was only distinguished from the Cynics by the elegance and
moderation of his tone. Even this narrow standing-ground became
untenable when exposed to the formidable competition of Stoicism. The
precept, Follow Nature, borrowed by the new philosophy from Polemo,
acquired a far deeper significance than he could give it, when viewed
in the light of an elaborate physical system showing what Nature was,
and whither her guidance led. But stone after stone had been removed
from the Platonic superstructure and built into the walls of other
edifices, only to bring its original foundation the more prominently
into sight. This was the initial doubt of Socrates, widened into the
confession of universal ignorance attributed to him by Plato in the
_Apologia_. Only by returning to the exclusively critical attitude
with which its founder had begun could the Academy hope to exercise
any influence on the subsequent course of Greek speculation. And it
was also necessary that the agnostic standpoint should be taken much
more in earnest by its new representatives than by Socrates or Plato.
With them it had been merely the preparation for a dogmatism even more
self-confident than that of the masters against whom they fought; but
if in their time such a change of front might seem compatible with
the retention of their old strongholds, matters now stood on a widely
different footing. Experience had shown that the purely critical
position could not be abandoned without falling back on some one or
other of the old philosophies, or advancing pretensions inconsistent
with the dialectic which had been illustrated by their overthrow. The
course marked out for Plato’s successors by the necessities of thought
might have been less evident had not Pyrrhonism suddenly revealed
to them where their opportunities lay, and at the same time, by its
extinction as an independent school, allowed them to step into the
vacant place.
It was at this juncture that the voluntary withdrawal of an older
fellow-pupil placed Arcesilaus at the head of the Academy. The date of
his accession is not given, but we are told that he died 241 or 240
B.C. in the seventy-fifth year of his age. He must, therefore, have
flourished a generation later than Zeno and Epicurus. Accomplished,
witty, and generous, his life is described by some as considerably less
austere than that of the excellent nonentities whom he succeeded. Yet
its general goodness was testified to by no less an authority than his
contemporary, the noble Stoic, Cleanthes. ‘Do not blame Arcesilaus,’
exclaimed the latter to an unfriendly critic; ‘if he denies duty
in his words, he affirms it in his deeds.’ ‘You don’t flatter me,‘
observed Arcesilaus. ‘It is flattering you,’ rejoined Cleanthes, ‘to
say that your actions belie your words.’[230] It might be inferred from
this anecdote that the scepticism of the new teacher, like that of
Carneades after him, was occasionally exercised on moral distinctions,
which, as then defined and deduced, were assuredly open to very serious
criticism. Even so, in following the conventional standard of the age,
he would have been acting in perfect consistency with the principles
of his school. But, as a matter of fact, his attacks seem to have been
exclusively aimed at the Stoic criterion of certainty. We have touched
on this difficult subject in a former chapter, but the present seems a
more favourable opportunity for setting it forth in proper detail.
The Stoics held, as Mr. Herbert Spencer, who resembles them in so
many respects, now holds, that all knowledge is ultimately produced
by the action of the object on the subject. Being convinced, however,
that each single perception, as such, is fallible, they sought for
the criterion of certainty in the repetition and combination of
individual impressions; and, again like Mr. Spencer, but also in
complete accordance with their dynamic theory of Nature, they estimated
the validity of a belief by the degree of tenacity with which it is
held. The various stages of assurance were carefully distinguished
and arranged in an ascending series. First came simple perception,
then simple assent, thirdly, comprehension, and finally demonstrative
science. These mental acts were respectively typified by extending the
forefinger, by bending it as in the gesture of beckoning, by clenching
the fist, and by placing it, thus clenched, in the grasp of the other
hand. From another point of view, they defined a true conviction as
that which can only be produced by the action of a corresponding real
object on the mind. This theory was complicated still further by the
Stoic interpretation of judgment as a voluntary act; by the ethical
significance which it consequently received; and by the concentration
of all wisdom in the person of an ideal sage. The unreserved bestowal
of belief is a practical postulate dictated by the necessities of life;
but only he who knows what those necessities are, in other words only
the wise man, knows when the postulate is to be enforced. In short, the
criterion of your being right is your conviction that you are right,
and this conviction, if you really possess it, is a sufficient witness
to its own veracity. Or again, it is the nature of man to act rightly,
and he cannot do so unless he has right beliefs, confirmed and clinched
by the consciousness that they are right.
Arcesilaus left no writings, and his criticisms on the Stoic theory, as
reported by Cicero and Sextus Empiricus, have a somewhat unsatisfactory
appearance. By what we can make out, he seems to have insisted on the
infallibility of the wise man to a much greater extent than the Stoics
themselves, not allowing that there was any class of judgments in which
he was liable to be mistaken. But just as the Stoics were obliged to
accept suicide as an indispensable safeguard for the inviolability
of their personal dignity and happiness, so also Arcesilaus had
recourse to a kind of intellectual suicide for the purpose of securing
immunity from error. The only way, according to him, in which the sage
can make sure of never being mistaken is never to be certain about
anything. For, granting that every mental representation is produced
by a corresponding object in the external world, still different
objects are connected by such a number of insensible gradations that
the impressions produced by them are virtually indistinguishable
from one another; while a fertile source of illusions also exists
in the diversity of impressions produced by the same object acting
on different senses and at different times. Moreover, the Stoics
themselves admitted that the sage might form a mistaken opinion; it
was only for his convictions that they claimed unerring accuracy, each
of the two—opinion and conviction—being the product of a distinct
intellectual energy. Here again, Arcesilaus employed his method of
infinitesimal transitions, refusing to admit that the various cognitive
faculties could be separated by any hard and fast line; especially
as, according to the theory then held by all parties, and by none
more strongly than the Stoics, intellectual conceptions are derived
exclusively from the data of sense and imagination. We can see that the
logic of Scepticism is, equally with that of the other Greek systems,
determined by the three fundamental moments of Greek thought. There
is first the careful circumscription of certainty; then there is the
mediating process by which it is insensibly connected with error;
and, lastly, as a result of this process, there is the antithetical
opposition of a negative to an affirmative proposition on every
possible subject of mental representation.[231]
To the objection that his suspensive attitude would render action
impossible, Arcesilaus replied that any mental representation was
sufficient to set the will in motion; and that, in choosing between
different courses, probability was the most rational means of
determination. But the task of reducing probable evidence to a system
was reserved for a still abler dialectician, who did not appear on the
scene until a century after his time. Arcesilaus is commonly called the
founder of the Middle, Carneades the founder of the New Academy. The
distinction is, however, purely nominal. Carneades founded nothing.
His principles were identical with those of his predecessor; and his
claim to be considered the greatest of the Greek sceptics is due to his
having given those principles a wider application and a more systematic
development. The Stoics regarded it as a special dispensation of
providence that Chrysippus, the organising genius of their school,
should have come between its two most formidable opponents, being
thus placed in a position to answer the objections of the one and to
refute by anticipation those of the other.[232] It might seem to less
prejudiced observers that the thinker whose cause benefited most by
this arrangement was Carneades. Parodying a well-known iambic, he used
to say:
‘Without Chrysippus I should not have been.’[233]
And, in fact, it was by a close study of that writer’s voluminous
treatises that he was able to cover the immense extent of ground
which Scepticism thenceforward disputed with the dogmatic schools.
Nor were his attacks directed against Stoicism only, but against all
other positive systems past and present as well. What he says about
the supposed foundation of knowledge is even now an unanswerable
objection to the transcendental realism of Mr Herbert Spencer. States
of consciousness speak for themselves alone, they do not include the
consciousness of an external cause.[234] But the grounds on which he
rests his negation of all certainty are still superficial enough,
being merely those sensible illusions which the modern science of
observation has been able either to eliminate altogether or to restrict
within narrow and definable limits. That phenomena, so far from being
necessarily referred to a cause which is not phenomenal, cannot be
thought of at all except in relation to one another, and that knowledge
means nothing more than a consciousness of this relation, was hardly
perceived before the time of Hume.
Turning from sense to reason, Carneades attacks the syllogistic process
on grounds already specified in connexion with the earlier Sceptics;
and also on the plea that to prove the possibility of syllogism is
itself to syllogise, and thus involves either a _petitio principii_
or a regress _ad infinitum_.[235] Such a method is, of course,
suicidal, for it disproves the possibility of the alleged disproof,
a consideration which the Stoics did not fail to urge, and which the
later Sceptics could only meet by extending the rule of suspense to
their own arguments against argument.[236] Nevertheless the sceptical
analysis detected some difficulties in the ordinary theory of logic,
which have been revived in modern times, and have not yet received
any satisfactory solution. Sextus Empiricus, probably copying an
earlier authority, it may be Carneades himself, observes that, as
the major premise of every syllogism virtually contains the minor,
it is either superfluous, or assumes the proposition to be proved.
Thus we argue that Socrates is an animal because he is a man, and all
men are animals. But if we do not know this latter proposition to be
true in the case of Socrates, we cannot be sure that it is true in
any case; while if we know it to be true in his case, we do not need
to begin by stating it in general terms. And he also attempts to show
the impossibility of a valid induction by the consideration, since so
often urged, that to generalise from a limited number of instances
to a whole class is unsafe, for some of the unknown instances may be
contradictory, while the infinite, or at least indefinite multiplicity
of individuals precludes the possibility of their exhaustive
enumeration.[237]
When the Academicians pass from the form to the matter of dogmatic
philosophy, their criticisms acquire greater interest and greater
weight. On this ground, their assaults are principally directed
against the theology of their Stoic and Epicurean rivals. It is here
in particular that Carneades reveals himself to us as the Hume of
antiquity. Never has the case for agnosticism been more powerfully
made out than by him or by the disciples whom he inspired. To the
argument for the existence of supernatural beings derived from
universal consent, he replies, first, that the opinion of the vulgar
is worthless, and secondly, that men’s beliefs about the gods are
hopelessly at variance with one another, even the same divinity being
made the subject of numberless discordant legends.[238] He reduces
the polytheistic deification of natural objects to an absurdity
by forcing it back through a series of insensible gradations into
absolute fetichism.[239] The personification of mental qualities
is similarly treated, until an hypothesis is provided for every
passing mood.[240] Then, turning to the more philosophical deism of
the Stoics, he assails their theory of the divine benevolence with
instance after instance of the apparent malevolence and iniquity to
be found in Nature; vividly reminding one of the facts adduced by Mr.
Herbert Spencer in confutation of the similar views held by modern
English theologians.[241] As against the whole theory of final causes,
Carneades argues after a method which, though logically sound, could
not then present itself with the authority which advancing science
has more recently shown it to possess. ‘What you Stoics,’ he says,
‘explain as the result of conscious purpose, other philosophers, like
Strato for instance, explain with equal plausibility as the result of
natural causation. And such is our ignorance of the forces at work in
Nature that even where no mechanical cause can be assigned, it would
be presumptuous to maintain that none can exist.[242] The reign of law
does not necessarily prove the presence of intelligence; it is merely
the evidence of a uniform movement quite consistent with all that we
know about the working of unconscious forces.[243] To contend, with
Socrates, that the human mind must be derived from a Universal Mind
pervading all Nature would logically involve the transfer of every
human attribute to its original source.[244] And to say that the
Supreme Being, because it surpasses man, must possess an intelligence
like his, is no more rational than to make the same assumption with
regard to a great city because it is superior to an ant.’[245]
The materialism of his dogmatic contemporaries placed them at a
terrible disadvantage when the sceptical successor of Plato went
on to show that eternal duration is incompatible with whatever we
know about the constitution of corporeal substance; and this part
of his argument applied as much to the Epicurean as to the Stoic
religion.[246] But even a spiritualistic monotheism is not safe from
his dissolving criticism. According to Carneades, a god without senses
has no experience of whatever pleasurable or painful feelings accompany
sensation, and is therefore, to that extent, more ignorant than a man;
while to suppose that he experiences painful sensations is the same
as making him obnoxious to the diminished vitality and eventual death
with which they are naturally associated. And, generally speaking,
all sensation involves a modification of the sentient subject by an
external object, a condition necessarily implying the destructibility
of the former by the latter.[247] So also, moral goodness is an
essentially relative quality, inconceivable without the possibility
of succumbing to temptation, which we cannot attribute to a perfect
Being.[248] In a word, whatever belongs to conscious life being
relative and conditioned, personality is excluded from the absolute by
its very definition.
As to the proofs of divine agency derived from divination, they are
both irrational and weak. If all things are predetermined by God’s
providence, knowledge of the future is useless, and, therefore, cannot
have been given to us. Moreover, no confidence can be placed in the
alleged fulfilments of prophecy; probably most of them are fictitious
and the remainder accidental. For the rest, good luck is distributed
without regard to merit; and the general corruption of mankind shows
that, from the Stoic point of view, human nature is a complete
failure.[249]
Well may M. Havet say of the Academicians: ‘ce sont eux et non les
partisans d’Epicure qui sont les libres penseurs de l’antiquité ou
qui l’auraient voulu être; mais ils ne le pouvaient pas.’[250] They
could not, for their principles were as inconsistent with an absolute
negation as with an absolute affirmation; while in practice their rule
was, as we have said, conformity to the custom of the country; the
consequence of which was that Sceptics and Epicureans were equally
assiduous in their attendance at public worship. It is, therefore,
with perfect dramatic appropriateness that Cicero puts the arguments
of Carneades into the mouth of Cotta, the Pontifex Maximus; and,
although himself an augur, takes the negative side in a discussion on
divination with his brother Quintus. And our other great authority on
the sceptical side, Sextus Empiricus, is not less emphatic than Cotta
in protesting his devotion to the traditional religion of the land.[251]
We have seen with what freedom Carneades discussed the foundations of
morality. It is now evident that in so doing he did not exceed the
legitimate functions of criticism. No one at the present day looks
on Prof. Bain and Mr. Henry Sidgwick as dangerous teachers because
they have made it clear that to pursue the greatest happiness of the
greatest number is not always the way to secure a maximum of happiness
for oneself. The really dangerous method, as we now see, is to foster
illusions in early life which subsequent experience must dispel.
With the introduction of practical questions, we pass to the great
positive achievement of Carneades, his theory of probable evidence.
Intended as an account of the process by which belief is adjusted
to safe action rather than of the process by which it is brought
into agreement with reality, his logic is a systematisation of the
principles by which prudent men are unconsciously guided in common
life. Carneades distinguishes three degrees of probability. The lowest
is attached to simple perception. This arises when we receive the
impression of an object without taking the attendant circumstances
into account. The next step is reached when our first impression is
confirmed by the similar impressions received from its attendant
circumstances; and when each of these, again, bears the test of a
similar examination our assurance is complete. The first belief is
simply probable; the second is probable and uncontradicted; the third
probable, uncontradicted, and methodically established. The example
given by Sextus is that of a person who on seeing a coil of rope in a
dark passage thinks that it may be a snake, and jumps over it, but on
turning round and observing that it remains motionless feels inclined
to form a different opinion. Remembering, however, that snakes are
sometimes congealed by cold in winter, he touches the coil with his
stick, and finally satisfies himself by means of this test that the
image present to his mind does not really represent a snake. The
circumstances to be examined before arriving at a definite judgment
include such considerations as whether our senses are in a healthy
condition, whether we are wide awake, whether the air is clear, whether
the object is steady, and whether we have taken time enough to be
sure that the conditions here specified are fulfilled. Each degree of
probability is, again, divisible into several gradations according
to the strength of the impressions received and the greater or less
consilience of all the circumstances involved.[252]
The Academic theory of probability bears some resemblance to the
Canonic of Epicurus, and may have been partially suggested by it. Both
are distinguished from the Aristotelian and Stoic logic by the care
with which they provide for the absence of contradictory evidence.
In this point, however, the superiority of Carneades to Epicurus
is very marked. It is not enough for him that a present impression
should suggest a belief not inconsistent with past experience; in the
true inductive spirit, he expressly searches for negative instances,
and recommends the employment of experiment for this purpose. Still
more philosophical is the careful and repeated analysis of attendant
circumstances, a precaution not paralleled by anything in the slovenly
method of his predecessor. Here the great value of scepticism as an
element in mental training becomes at once apparent. The extreme
fallibility of the _intellectus sibi permissus_ had to be established
before precautions could be adopted for its restraint. But the
evidence accepted in proof of this fallibility has been very different
at different times, and has itself given rise to more than one
fallacious interpretation. With us it is, for the most part, furnished
by experience. The circumstance that many demonstrable errors were
formerly received as truths is quite sufficient to put us on our guard
against untested opinions. With Bacon, it was not the erroneousness
of previous systems, but their barrenness and immobility, which led
him to question the soundness of their logic; and his doubts were
confirmed by an analysis of the disturbing influences under which men’s
judgments are formed. The ancient Sceptics were governed entirely by
_à priori_ considerations. Finding themselves confronted by an immense
mass of contradictory opinions, they argued that some of these must be
false as all could not possibly be true. And an analysis of the human
faculties led them, equally on _à priori_ grounds, to the conclusion
that these irreconcilable divergences were but the result and the
reproduction of an interminable conflict carried on within the mind
itself. They could not foresee how much time would do towards reducing
the disagreement of educated opinion within a narrower compass. They
did not know what the experience of experience itself would teach.
And their criticisms on the logic and metaphysics of their opponents
were rendered inconclusive, as against all certainty, by the extent to
which they shared that logic and metaphysics themselves. Carneades, at
least, seems to assume throughout that all existence is material, that
there is a sharp distinction between subject and object in knowledge,
and that there is an equally sharp distinction between sensation and
reasoning in the processes by which knowledge is obtained. In like
manner, his ethical scepticism all turns on the axiom, also shared by
him with the Stoics, that for a man to be actuated by any motive but
his own interest is mere folly.