XXXVIII--SYLLOGISM

We have already had two distinct definitions of syllogism. According

to the first it is the application of class-attributes to individuals

known to belong to the class; according to the second it is the

comparison of two things or terms by reference to a third which both

resemble. When we arrive at the chapters in logic books devoted to the

exposition of the syllogism in detail, we find that the theorems there

discussed do not conform to either of those definitions. The only

sort of syllogism that can be 'converted' is one consisting of two

classifications, and a conclusion which predicates a classification,

as thus--

_All Englishmen are Europeans;

John Smith is an Englishman;

therefore John Smith is a European._

Observe the difference between this theorem and that adduced in

illustration of the Dictum (XXXVI). In the latter the first premise

is a categorical judgment and so therefore is the conclusion; in the

theorem just given the first premise is a classification, and the

conclusion is necessarily a classification.

We first remark that such an 'argument' is never met with in

real spontaneous thinking--it occurs only in logic books. It is

manufactured exclusively for Peripatetic consumption. The reason it

is not to be found is simple--the conclusion it yields is a

classification, and that is not enough for valid argument.

In reasoning we may introduce a classification as the _minor

premise_--that is, the proposition which brings the case under the

precedent--but the applicate is never a general or class idea. It is

one or more properties abstracted from the subject (whether the latter

be a single object or general idea), and applied to the case. Merely

to classify a case and so leave it would answer no rational purpose.

Logicians urge in recommendation of this syllogism that it gives a

certain conclusion. The premises being correct, the conclusion is

infallibly true.

No doubt it is, for in contemplating a thing we can mentally enter it

into all the classes to which it appears to belong, whatever be their

generality. Knowing the class European and the individual John Smith,

we see at once that the latter is contained in the former, and we can

do this without putting him first in the minor class English. It is

like saying, 'The pavilion is in the garden, John Smith is in the

pavilion, therefore he is in the garden.' Of course he is! The minor

premise of a double classification is superfluous. The fact that

such conclusions are certain, shows how nugatory they are. We are

not certain of anything till it has been experienced. In legitimate

reasoning the conclusion is never more than probable. The certainty of

these double classifications shows that we are stating what we already

know--not imagining an ideal addition to our positive knowledge.

_Doctrine of the Predicate._ So long as logicians are permitted to

fabricate their own examples, all is plain sailing with the syllogism.

But they are sometimes obliged to deal with genuine arguments. In

this case what they do is to assume that _for logical purposes_ every

predicate of the precedent--that is, the applicate--is a general or

class term. Even when an argument is good they spoil it with a bad

theory.

Sir William Hamilton states that up to his time logicians recognised

but one type of proposition--that called by him the proposition 'in

extension,' which means the classifying of the subject. He announced

that he intended to introduce a proposition 'in comprehension,'

meaning a judgment in the category of inherence--as for instance, 'man

is responsible.' He further said that he recognised a third type of

proposition, that concerning 'cause and effect.'

But in the course of working out these logical novelties he seems to

have discovered that they were irreconcilable with conversion, and so

he dropped them. The judgment in comprehension, he then declared, was

to all intents and purposes the same as one in extension, and as to

causation--why, a cause is a class, and an effect is an individual

belonging to that class![22]

Let us see what is the result of treating applicates as general ideas.

Take an example in each of the categories.

'The paper is white.' This means that the paper has the property or

attribute of whiteness. In logic it is interpreted to mean that paper

is an individual of the class _white_. This is wrong, for there is no

such class. No sane person would form a class out of salt, snow, milk,

china, silver, the moon, and other white things; for though they have

a common property it is not the sign of a common human utility.

The confusing a single property with a class is not always owing to

exigencies of syllogism. It pervades the writings of most Western

metaphysicians, and may be accounted for in this manner.

General ideas and abstract properties or ideas have in common that

they are _partial_ recognitions of what we perceive (XIV). The

partition in each is however made in a different way, and for a

different purpose. In generalisation the selection is done almost

mechanically. We see many things that have some common relation,

function, or utility for us, and we remember only so much of them

as appears to be necessary for the recognition of that relation or

utility--just so much of the Intellectual experience as has always

accompanied the Sentimental experience. The process is very like that

of putting a piece of wood or ivory in a turning-lathe, and whittling

off all that we do not want. A general idea is the useful core of

a multitude of superposed observations, each of which had something

irrelevant--something which it is better to forget. We whittle this

off and remember only the core.

Abstraction, on the other hand, is a conscious and deliberate

operation from beginning to end. It consists in distinguishing one by

one the properties of a thing, and even treating each property as if

it had an independent existence. For this exercise it is not

necessary to observe many things: we can analyse one alone, though an

acquaintance with other cognate objects is sometimes necessary to call

our attention to single properties. We need the shock of difference to

be able to distinguish well a fine abstraction--the difference between

shades of colours, for example. Abstraction is thus a minute

attention to individuals, and need not for a moment be confounded with

generalisation.

Another cause of the confusion in question can be traced to the use of

the verb 'is' to represent both the relation of a thing to the general

idea it has contributed to form, and the relation of a single property

to the thing in which it inheres. We say 'The man _is_ a British

subject'--classifying him; we say also 'The man _is_ cold'--mentioning

one of his attributes. There is no class of cold men, and the two

relations have nothing in common. A class does not inhere in a man as

cold inheres in him. There is no _object_ corresponding to class--it

is a conceptual creation.

The ambiguity of 'is' favours the syllogistic doctrine of predication,

and there is a rule to the effect that in syllogising propositions,

all verbs are to be converted into 'is' (or its conjugates) with a

participle or noun, so that if they were not before statements

of classification they now become such. 'He walks' is clearly no

classification; but 'he is walking' is assimilated by false analogy

to such a classification as 'he is human,' and so is treated as a

classification by those who reason according to the Letter.

The substantive verb has no positive and uniform meaning. As an

auxiliary it is a mere sign of tense, and in other positions it is an

indefinite mark of relationship, the precise meaning of which must

be determined by the subject and the context. It may sometimes be

dispensed with in classification, as 'Victoria Regina'--'Phillips,

Dentist.'

In the second category we have such propositions as 'the book lies on

the table.' In syllogistic this is first altered to 'the book is lying

on the table,' and it is feigned that 'lying on the table' is a class

or general idea, and 'book' an individual of that class. To interpret

'the groom stands by the horse' a class has to be created, composed of

the persons who happen to be standing by horses.

'The mountain is ten miles off' is a judgment in perspection.

Syllogistically we are asked to believe that a class of things exists

having the common property of being ten miles off, and that the

mountain is entered in that class. The absurdity of this doctrine is

self-evident.

In the remaining categories the reduction to 'is' has, if possible, a

worse effect. In changing 'Canada lies west of Ireland' into

'Canada is a country lying west of Ireland,' we lose the relation

in concretion, and express instead a verbal definition. Instead of

affirming a position we explain a name. In such a proposition as 'the

town of A lies 100 miles due north of B,' it is plain the predicate

cannot be a class, for only one place has the quality expressed.

In the fifth category we have such a proposition as 'water freezes

when the temperature falls to zero Centigrade.' This is turned into a

substantive sentence by saying 'water is that liquid which freezes,'

&c., which is a verbal or identical proposition.

'Cecrops founded Athens' is a judgment in causation. In turning it

into 'Cecrops was (or is) the founder of Athens,' we emphasise the

man's name, but the relation signified by 'founded' is slurred over

or lost sight of. Boole converts 'Caesar conquered the Gauls' into

'Caesar is he who conquered the Gauls,'[23] and this he interpreted

as classification. We need not be surprised that he should suppose

a class could be formed by one individual, for he elsewhere tells us

that _Nothing_ is a class.[24]

Classification is not judgment of any sort--it is a variety of

recollection. Logicians imagine it is the only judgment, and so far as

they can they degrade true judgments to that spurious form.

_Moods of the Syllogism._ Having persuaded themselves that

classification is the beginning, middle, and end of reasoning,

logicians next proceed to divide the matter of their science.

Modern logicians who have some acquaintance with real thinking as

exemplified in works of physical science, can, if acting according

to their natural intelligence, lay down correct rules for dividing a

subject. These are simple and obvious: divide according to fundamental

resemblance--let each division correspond to some definite human

utility--let the more important properties take precedence of the less

important, and so forth: the merest common sense.

But in the division of their own subject they follow Aristotle, and so

lose their way.

It is plain that an act of reasoning is a mental thing in the first

place, and only when uttered, and thus in a secondary sense, is it

a material object. The classification of arguments should therefore

follow mental characteristics. Logicians make it follow the material

characteristics of the terms in which the arguments are uttered. Their

moods of the syllogism are mere varieties of expression, not varieties

of reason.

The number of these moods is accidental, depending on flexibility

of language and ingenuity in inventing varieties of syntax. Mere

transposition of premises constitutes a difference of mood. Logicians

however pretend to base their numeration on a more general necessity.

They calculate from the distinctive parts of the three propositions

forming a syllogism, varied by negation, &c., that there _ought to be_

sixty-four moods. Experience proves that in spite of their free and

easy method of multiplying syllogistic varieties they cannot produce

anything like that number. One logician has thirty-six moods, another

thirty-two, a third eleven; the more orthodox fix the number at

nineteen. But they all admit that every argument can be reduced to

one of four fundamental types--the moods of the First Figure. Why then

have more classes than these four? Because, says Whately, it would be

'occasionally tedious' to reduce every argument to the first figure.

If the 11, 19, 32, or 36 classes were natural arguments taken

down untouched from men's lips, and it was found to be useless and

troublesome to reduce them to four artificial forms, the plea might

be admitted. But the so-called valid syllogisms are themselves

artificial, and just as tedious to make as the moods of the first

figure. Not only so, but an elaborate system of mnemonic rules is

provided for reducing the valid moods to the fundamental moods, thus

admitting that the former are only intermediate halting places between

the natural speech and the fundamental moods. It is _expected_ that

the intermediates should be reduced to the first figure.

Is there anything analogous to this sort of division in any science or

branch of practical thought? Would logicians themselves sanction such

a classification in a natural science? If a zoologist, for example,

were to determine beforehand how many classes of animals there

ought to be, would they not say he was acting improperly? If, after

discovering that he had five times as many classes as he could find

animals to put into them, he still retained his classification and

required his pupils to write out the names or symbols of all the

useless classes--would not logicians be apt to call him a pedant? Yet

in a modern work on logic such a task is prescribed for students:--

'Write out the sixty-four moods of the syllogism, _and strike

out the fifty-three invalid ones_.'

We might have excused the existence of a merely verbal classification

in logic, if it were accompanied by and subordinated to a

classification of theorems considered as mental facts. But in

syllogistic the verbal is the dominant classification, and we have

seen from the procedure of Sir William Hamilton--in dropping his

categorical judgments--that when the two principles of division

conflict, it is the mental which has to give way. The Letter is

allowed to kill the Spirit.

_All the Moods reducible to One._ Syllogists appear not to know their

own schematism very well. They say there are four ultimate moods,

which it is impossible to reduce to any lower number. But since each

of the four is, mentally, a double classification, it must be possible

to reflect this common property in the mode of expression. The

difference between them can only be verbal. Let us adopt another than

the ordinary symbolism.

Cut a card into three triangular pieces of unequal size, and call

them by the letters A, B, C, beginning with the largest. These are the

terms of the syllogism.

A A

/\B /\ B

/ /\C / \ /\C

/ / /\ / \ / /\

/ / / \ / \ / / \

/ / / \ / \ / / \

/ / / \ / \ / / \

+------------+ +------------+ +----------+

_Barbara._ _Celarent._

A A

/\B /\ B

/ /\ C / \ /\ C

/ / \ : / \ / \ :

/ / \: : / \ / \: :

/ / /\ : / \ / /\ :

/ / / \ : / \ / / \ :

+------------+... +------------+ +----------+...

_Darii._ _Ferio._

The first mood _Barbara_ is formed by placing the cards on top of each

other, so that B is within the margin of A, and C within the margin of

B. This is the syllogism, 'All B is A, all C is B, therefore all C is

A.'

Next let B and C be as above, but let A be wholly apart from both.

This is _Celarent_: 'No B is A, all C is B, therefore no C is A.'

In _Darii_ the whole of B is in A, but only a part of C coincides with

B. The syllogism is: 'All B is A, some C is B, therefore some C is A.'

In _Ferio_ A is again wholly separated from the others, and C is only

partially in B. Argument: 'No B is A, some C is B, therefore some C is

not A.'

It is to be remembered that all the other figures and moods are

reducible to the above figure of four moods, so that the reduction

applicable to the latter is equally applicable to the former.

To reduce _Darii_ to _Barbara_ all that is necessary is to ignore the

dotted part of C. That is suggested by the use of the word 'some,'

which has a correlative 'all' or 'others.' But the correlative

quantity does not enter into the syllogism, and we know nothing about

it. It may not even exist. We are therefore at liberty to substitute

for 'some C' the name D, and consider it an integer instead of a

fraction. Then we have the _Barbara_ syllogism: 'All B is A, all D (=

some C) is B, therefore all D is A.' The phrase 'all of some' is quite

allowable: 'I met some firemen, all of whom wore brass helmets.'

_Ferio_ in the same manner is reduced to _Celarent_. The dotted part

of C is cut away, and the part really significant in the syllogism is

called E. Then 'No B is A, all E is B, no E is A.'

Finally _Celarent_ can be reduced to _Barbara_. B cannot indeed be

enclosed in A, but we assume the existence of a whole having all the

characters which A has _not_, or having none of the characters which

A has. This is the whole F = Not-A. Then _Celarent_ becomes _Barbara_

thus: 'All B is F, all C is B, therefore all C is F.'

This demonstrates that there is only one fundamental operation where

syllogists suppose there are at least four. The difference is wholly a

matter of language, and disappears on changing the names of the terms

and ignoring irrelevant suggestions. But the syllogism, I repeat, does

not represent the act of reasoning, and its moods and figures are fit

only to be a game for children.

[Footnote 20: _Logic_, Book I. § 3.]

[Footnote 21: _Logic_, Book II. c. 3. § 2.]

[Footnote 22: _Lectures_, iii. pp. 287 and 356. The

impossibility of reconciling their definitions and rules to

real thinking and argument is the despair of logicians. Most

of them take to symbols, which are more accommodating than

real experience, having just such properties as their makers

choose to put in them. Sir William Hamilton had the courage to

declare that a logician might use arguments of a concrete or

real form, but that it is not necessary they should agree with

real fact. 'The logician has a right to suppose any material

impossibility, any material falsity; he takes no account of

what is objectively impossible or false, he has a right to

assume what premises he please, provided that they do not

involve a contradiction in terms.'--_Id._ 322. That means

in plain English that a logician may misrepresent matters of

fact, if he cannot otherwise establish his theory!]

[Footnote 23: _Laws of Thought_, p. 35.]

[Footnote 24: _Ibid._ p. 47.]

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