The Lives and Opinions of Eminent Philosophers
He has written a great many books, of which I have already given a list,
in which he has spoken as no other of the Stoics has. And his doctrines
in general are these. But we will enumerate them briefly, as we have been
in the habit of doing in the case of the other philosophers.
XXXIII. The Stoics divide reason according to philosophy, into three
parts; and say that one part relates to natural philosophy, one to
ethics, and one to logic. And Zeno, the Cittiæan, was the first who made
this division, in his treatise on Reason; and he was followed in it by
Chrysippus, in the first book of his treatise on Reason, and in the first
book of his treatise on Natural Philosophy; and also by Apollodorus; and
by Syllus, in the first book of his Introduction to the Doctrines of the
Stoics; and by Eudromus, in his Ethical Elements; and by Diogenes, the
Babylonian; and Posidonius. Now these divisions are called _topics_ by
Apollodorus, _species_ by Chrysippus and Eudromus, and _genera_ by all
the rest. And they compare philosophy to an animal, likening logic to the
bones and sinews, natural philosophy to the fleshy parts, and ethical
philosophy to the soul. Again, they compare it to an egg; calling logic
the shell, and ethics the white, and natural philosophy the yolk. Also to
a fertile field; in which logic is the fence which goes round it, ethics
are the fruit, and natural philosophy the soil, or the fruit-trees.
Again, they compare it to a city fortified by walls, and regulated by
reason; and then, as some of them say, no one part is preferred to
another, but they are all combined and united inseparably; and so they
treat of them all in combination. But others class logic first, natural
philosophy second, and ethics third; as Zeno does in his treatise on
Reason, and in this he is followed by Chrysippus, and Archedemus, and
Eudromus.
For Diogenes of Ptolemais begins with ethics; but Apollodorus places
ethics second; and Panætius and Posidonius begin with natural philosophy,
as Phanias, the friend of Posidonius asserts, in the first book of his
treatise on the School of Posidonius.
But Cleanthes says, that there are six divisions of reason according
to philosophy: dialectics, rhetoric, ethics, politics, physics, and
theology; but others assert that these are not divisions of reason,
but of philosophy itself; and this is the opinion advanced by Zeno, of
Tarsus, among others.
XXXIV. Some again say, that the logical division is properly subdivided
into two sciences, namely, rhetoric and dialectics; and some divide
it also into definitive species, which is conversant with rules and
tests; while others deny the propriety of this last division altogether,
and argue that the object of rules and tests is the discovery of the
truth; for it is in this division that they explain the differences of
representations. They also argue that, on the other side, the science of
definitions has equally for its object the discovery of truth, since we
only know things by the intervention of ideas. They also call rhetoric
a science conversant about speaking well concerning matters which admit
of a detailed narrative; and dialectics they call the science of arguing
correctly in discussions which can be carried on by question and answer;
on which account they define it thus: a knowledge of what is true, and
false, and neither one thing nor the other.
Again, rhetoric itself they divide into three kinds; for one description
they say is concerning about giving advice, another is forensic, and
the third encomiastic; and it is also divided into several parts,
one relating to the discovery of arguments, one to style, one to the
arrangement of arguments, and the other to the delivery of the speech.
And a rhetorical oration they divide into the exordium, the narration,
the reply to the statements of the adverse party, and the peroration.
XXXV. Dialectics, they say, is divided into two parts; one of which has
reference to the things signified, the other to the expression. That
which has reference to the things signified or spoken of, they divide
again into the topic of things conceived in the fancy, and into those
of axioms, of perfect determinations, of predicaments, of things alike,
whether upright or prostrate, of tropes, of syllogisms, and of sophisms,
which are derived either from the voice or from the things. And these
sophisms are of various kinds; there is the false one, the one which
states facts, the negative, the sorites, and others like these; the
imperfect one, the inexplicable one, the conclusive one, the veiled one,
the horned one, the nobody, and the mower.
In the second part of dialectics, that which has for its object the
expression, they treat of written language, of the different parts of a
discourse, of solecism and barbarism, of poetical forms of expression, of
ambiguity, of a melodious voice, of music; and some even add definitions,
divisions, and diction.
They say that the most useful of these parts is the consideration of
syllogisms; for that they show us what are the things which are capable
of demonstration, and that contributes much to the formation of our
judgment, and their arrangement and memory give a scientific character
to our knowledge. They define reasoning to be a system composed of
assumptions and conclusions: and syllogism is a syllogistic argument
proceeding on them. Demonstration they define to be a method by which
one proceeds from that which is more known to that which is less.
Perception, again, is an impression produced on the mind, its name
being appropriately borrowed from impressions on wax made by a seal;
and perception they divide into comprehensible and incomprehensible:
Comprehensible, which they call the criterion of facts, and which
is produced by a real object, and is, therefore, at the same time
conformable to that object; Incomprehensible, which has no relation
to any real object, or else, if it has any such relation, does not
correspond to it, being but a vague and indistinct representation.
Dialectics itself they pronounce to be a necessary science, and a virtue
which comprehends several other virtues under its species. And the
disposition not to take up one side of an argument hastily, they defined
to be a knowledge by which we are taught when we ought to agree to a
statement, and when we ought to withhold our agreement. Discretion they
consider to be a powerful reason, having reference to what is becoming,
so as to prevent our yielding to an irrelevant argument. Irrefutability
they define to be a power in an argument, which prevents one from being
drawn from it to its opposite. Freedom from vanity, according to them, is
a habit which refers the perceptions back to right reason.
Again, they define knowledge itself as an assertion or safe
comprehension, or habit, which, in the perception of what is seen, never
deviates from the truth. And they say further, that without dialectic
speculation, the wise man cannot be free from all error in his reasoning.
For that that is what distinguishes what is true from what is false, and
which easily detects those arguments which are only plausible, and those
which depend upon an ambiguity of language. And without dialectics they
say it is not possible to ask or answer questions correctly. They also
add, that precipitation in denials extends to those things which are
done, so that those who have not properly exercised their perceptions
fall into irregularity and thoughtlessness. Again, without dialectics,
the wise man cannot be acute, and ingenious, and wary, and altogether
dangerous as an arguer. For that it belongs to the same man to speak
correctly and to reason correctly, and to discuss properly those subjects
which are proposed to him, and to answer readily whatever questions
are put to him, all which qualities belong to a man who is skilful in
dialectics. This then is a brief summary of their opinions on logic.
XXXVI. And, that we may also enter into some more minute details
respecting them, we will subjoin what refers to what they call their
introductory science, as it is stated by Diocles, of Magnesia, in his
Excursion of Philosophers, where he speaks as follows, and we will give
his account word for word.
The Stoics have chosen to treat, in the first place, of perception
and sensation, because the criterion by which the truth of facts is
ascertained is a kind of perception, and because the judgment which
expresses the belief, and the comprehension, and the understanding of
a thing, a judgment which precedes all others, cannot exist without
perception. For perception leads the way; and then thought, finding vent
in expressions, explains in words the feelings which it derives from
perception. But there is a difference between φαντασία and φάντασμα. For
φάντασμα is a conception of the intellect, such as takes place in sleep;
but φαντασία is an impression, τύπωσις, produced on the mind, that is
to say, an alteration, ἀλλοίωσις, as Chrysippus states in the twelfth
book of his treatise on the Soul. For we must not take this impression
to resemble that made by a seal, since it is impossible to conceive that
there should be many impressions made at the same time on the same thing.
But φαντασία is understood to be that which is impressed, and formed,
and imprinted by a real object, according to a real object, in such a
way as it could not be by any other than a real object; and, according
to their ideas of the φαντασίαι, some are sensible, and some are not.
Those they call sensible, which are derived by us from some one or more
senses; and those they call not sensible, which emanate directly from the
thought, as for instance, those which relate to incorporeal objects, or
any others which are embraced by reason. Again, those which are sensible,
are produced by a real object, which imposes itself on the intelligence,
and compels its acquiescence; and there are also some others, which are
simply apparent, mere shadows, which resemble those which are produced by
real objects.
Again, these φαντασίαι are divided into rational and irrational; those
which are rational belong to animals capable of reason; those which are
irrational to animals destitute of reason. Those which are rational
are thoughts; those which are irrational have no name; but are again
subdivided into artificial and not artificial. At all events, an image is
contemplated in a different light by a man skilful in art, from that in
which it is viewed by a man ignorant of art.
By sensation, the Stoics understand a species of breath which proceeds
from the dominant portion of the soul to the senses, whether it be a
sensible perception, or an organic disposition, which, according to
the notions of some of them, is crippled and vicious. They also call
sensation the energy, or active exercise, of the sense. According to
them, it is to sensation that we owe our comprehension of white and
black, and rough and smooth: from reason, that we derive the notions
which result from a demonstration, those for instance which have for
their object the existence of Gods, and of Divine Providence. For all
our thoughts are formed either by indirect perception, or by similarity,
or analogy, or transposition, or combination, or opposition. By a direct
perception, we perceive those things which are the objects of sense; by
similarity, those which start from some point present to our senses; as,
for instance, we form an idea of Socrates from his likeness. We draw our
conclusions by analogy, adopting either an increased idea of the thing,
as of Tityus, or the Cyclops; or a diminished idea, as of a pigmy. So,
too, the idea of the centre of the world was one derived by analogy
from what we perceived to be the case of the smaller spheres. We use