Now the common logical judgments which we shall have to analyse

and classify are simply those parts of this continuous affirmation

of consciousness which are from time {41} to time separately made

distinct. Each of them therefore must be regarded as a partial

expression of the nature of reality, and the subject will always be

Reality in one form, and the predicate reality in another form. The

ultimate and complete judgment would be the whole of Reality predicated

of itself. All our logical judgments are such portions and fragments

of this judgment as we can grasp at the moment. Some of these gather

up in a system whole provinces of reality, others merely enlarge,

interpret, or analyse the content of a very simple sense-perception.

We shall not go far wrong in practice if we start from this judgment

of Perception as the fundamental kind of Judgment. The real subject in

Judgment is always Reality in some particular datum or qualification,

and the tendency of Judgment is always to be a definition of Reality.

We see the parts of Judgment most clearly in such thoughts as “This is

blue”; “This is a flower”; “That light is the rising sun”; “That sound

is the surf on a sandy shore.” In these we can plainly distinguish the

element of presentation and the interpretative construction or analytic

synthesis which is by the judgment identified with it.

{42}

LECTURE III THE RELATION OF LOGIC TO KNOWLEDGE

_Meaning of “Form”_

1. I spoke of the whole world, which we take to be real, as presented

to us in the shape of a continuous judgment. It is the task of Logic

to analyse the structure of this Judgment, the parts of which are

Judgments.

The first thing is then to consider what sort of properties of

Judgments we attend to in Logic. It is commonly said that Logic is a

formal science; that is, that it deals with the form, and not with the

content or matter of knowledge.

This word “form” is always meeting us in philosophy. “Species” is Latin

for form, as εἶδος and ἰδεα [1] are Greek for form. The form of any

object primarily means its appearance, that which the mind can carry

away, while the object as a physical reality, as material, remains

where it was. It need not mean shape as opposed to colour; that is a

narrower usage. The Greek opinion was no doubt rooted in some such

notion as that in knowing or remembering a thing the mind possessed

its form or image without its matter. Thus the form came to stand for

the knowable shape or structure which makes a thing what it is, and by

which we recognise it when we see it. This was its species or its idea,

the “image,” as it is used in the phrase, “Let us make man in our own

image.” So in any work of the hands {43} of man, the form was the shape

given by the workman, and came out of his mind, while the matter was

the stuff or material out of which the thing was made.

[1] [= “eidos” and “idea”. Tr.]

The moment we contemplate a classification of the sciences, we see

that this is a purely relative distinction. There is no matter without

form. If it was in this deep sense without form, it would be without

properties, and so incapable of acting or being acted upon. In a

knife the matter is steel, the form is the shape of the blade. But

the qualities of steel again depend, we must suppose, upon a certain

character and arrangement in its particles, and this is, as Bacon would

have called it, the _form_ of steel. But taken as purely relative,

the distinction is good _prima facie_. Steel has its own form, but

the knife has its form, and the matter steel can take many other

forms besides that of a knife. Marble has its own form, its definable

properties as marble (chemical and mechanical), but in a statue, marble

is the matter, and the form is the shape given by the sculptor.

Now applying this distinction to knowledge in general, we see that

all science is formal, and therefore it is no distinction to say that

Logic is a formal science. Geometry is a formal science; even molecular

physics is a formal science. All science is formal, because all science

consists in tracing out the universal characteristics of things, the

structure that makes them what they are.

The particular “form,” then, with which a science deals is simply the

kind of properties that come under the point of view from which that

science in particular looks at things. But a very general science is

more emphatically formal than {44} a very special science. That is to

say, it deals with properties which are presented in some degree by

everything; and so in every object a great multitude of properties

are disregarded by it, are treated by it as matter and not as form.

In this sense Logic is emphatically “formal,” though not nearly so

formal as it is often supposed to be. The subject-matter of Logic,

then, is Knowledge _qua_ Knowledge, or the form of knowledge; that is,

the properties which are possessed by objects or ideas _in so far as

they are members of the world of knowledge_. And it is quite essential

to distinguish the form of knowledge in this sense from its matter or

content. The “matter” of knowledge is the whole region of facts dealt

with by science and perception. If Logic dealt with this in the way in

which knowledge deals with it, _i.e._ simply as a process of acquiring

and organising experience, then Logic would simply be another name for

the whole range of science, history, and perception. Then there would

be no distinction between logic and science or common sense, and in

trying to ascertain, say, the wave-length of red light, or the cab-fare

from Chelsea to Essex Hall, we should be investigating a logical

problem. But we see at once that this is not what we mean by studying

knowledge as knowledge. Science or common sense aims at a particular

answer to each problem of this kind. Logic aims at understanding

the type and principles both of the problem and of its answer. The

details of the particular answer are the “_matter_ of fact.” The type

and principles which are found in all such particular answers may be

regarded as the form of fact, _i.e._ that which makes the fact a fact

in knowledge.

Jevons appears to me to make a terrible blunder at this {45} point. He

says [1]--“One name which has been given to Logic, namely the Science

of Sciences, very aptly describes the all-extensive power of logical

principles. The cultivators of special branches of knowledge appear

to have been fully aware of the allegiance they owe to the highest

of the sciences, for they have usually given names implying this

allegiance. The very name of Logic occurs as part of nearly all the

names adopted for the sciences, which are often vulgarly called the

‘ologies,’ but are really the ‘logics,’ the ‘o’ being only a connecting

vowel or part of the previous word. Thus geology is logic applied to

explain the formation of the earth’s crust; biology is logic applied

to the phenomena of life; psychology is logic applied to the nature

of the mind; and the same is the case with physiology, entomology,

zoology, teratology, morphology, anthropology, theology, ecclesiology,

thalattology, and the rest. Each science is thus distinctly confessed

to be a special logic. The name of Logic itself is derived from the

common Greek word λόγος, which usually means _word_, or the sign and

outward manifestation of any inward thought. But the same word was

also used to denote the inward thought or reasoning of which words are

the expression, and it is thus probably that later Greek writers on

reasoning were led to call their science ἐπιστήμη λογική, or logical

science, also τέχνη λογική or logical art. [2] The adjective λογική,

being used alone, soon came to be the name of the science, just as

Mathematic, Rhetoric, and other names ending in ‘ic’ were originally

adjectives, but have been converted into substantives.”

[1] _Elementary Lessons_, p. 6.

[2] [= “logos”, “episteme logike”, “techne logike” and “logike”. Tr.]

{46} This account of the connection between the name “Logic” and the

terminations of the names of the sciences appears precisely wrong.

Whatever may have been the exact meaning of the expression “Logic,”

or “Logical curriculum,” [1] or “art,” or “science” when first

employed, there can be no doubt that the word logical had a substantive

reference to that about which the science or teaching in question

was to treat. The term “logic,” therefore, corresponds not to the

syllables “logy” in such a word as “Zoology,” but to the syllables

“Zoo,” which indicate the province of the special science, and not

its character as a science. Zoology means connected discourse (λόγος)

about living creatures. Logic meant a curriculum, or science or art

dealing with connected discourse. The phrase “Science of Sciences,”

rightly interpreted, has the same meaning. It does not mean that Logic

is a Science which comprises all the special sciences, but that Logic

is a Science dealing with those general properties and relations which

all sciences _qua_ sciences have in common, but omitting, as from its

point of view matter and not form, the particular details of content by

which every science answers the particular questions which it asks. It

is wild, and most mischievous, to say that “every science is a special

logic,” or that “biology is Logic applied to the phenomena of life.”

This confusion destroys the whole disinterestedness which is necessary

to true scientific Logic, and causes the logical student always to have

his eye on puzzles, and special methods, and interferences by which he

may teach the student of science how to perform the concrete labour

of research. We quite admit that {47} a looker-on may _sometimes_ see

more of the game, and no wise investigator would contemn _a priori_

the suggestions of a student like Goethe, or Mill, or Lotze, because

their author was not exclusively engaged in the observation of

nature. But all this is secondary. The idea that Logic is a judge of

scientific results, able to pass sentence, in virtue of some general

criterion, upon their validity and invalidity, arises from a deep-lying

misconception of the nature of truth which naturally allies itself with

the above confusion between Logic and the special sciences.

[1] πραγμάτεια [= pragmateia Tr.]. See Prantl, i. 545.

Therefore the relation between content or matter of knowledge, and

the form which is its general characteristic as knowledge, is of

this kind. We can either study the objects of knowledge directly as

we perceive them, or indirectly, as examples of the way in which we

know. As studied for their own sake, they are regarded as the matter

or content in which the general form of knowledge finds individual

realisation. In botany, for instance, we have a large number of actual

plants classified and explained in their relation to one another.

A botanist is interested directly in the affinities and evolution

of these plants, and in the principles of biology which underlie

their history. He pushes his researches further and further into

the individual matters that come to light, without, as a rule, more

than a passing reflection upon the abstract nature of the methods

which he is creating as his work proceeds. He classifies, explains,

observes, experiments, theorises, generalises, to the best of his

power, solely in order to grasp and render intelligible the region of

concrete fact that lies before him. Now while his particular results

and discoveries {48} constitute the “form” or knowable properties of

the plant-world _as the object of botanical science_, the science

which inquires into the general nature of knowledge must treat these

particular results as “mere matter”--as something with which it is

not directly concerned, any more than the art which makes a statue

is primarily and directly concerned with the chemical and mechanical

properties of marble. The “form” or knowable properties with which the

general science of knowledge is directly concerned, consists in those

methods and processes which the man of science, developing the modes

in which common sense naturally works, constructs unconsciously as he

goes along. Thus, not the nature and affinities of the plant-world,

but classification, explanation, observation, experiment, theory, are

the phenomena in virtue of which the organised structure of botanical

science participates in the form of knowledge, and its objects become,

in these respects, objects of logical theory.

Hence some properties and relations of objects, being the form or

knowable structure of the concrete objects as a special department of

nature, correspond to the mere matter, stuff, or content of Knowledge

in general, while other properties and relations of objects, being

their form or knowable structure as entering into a world of reality

displayed to our intelligence, correspond to the form of Knowledge as

treated of by a general inquiry into its characteristics, which we

call Logic. It is just as the qualities or “forms” of the different

metals of which knives can be made are mere matter or irrelevant detail

when we are discussing the general “form” or quality of a good knife,

{49} whatever its material. A reservation on this head appears in the

following section.

_Form of Knowledge dependent on Content_

2. For the form of Knowledge depends in some degree upon its matter.

It is very important to realise this truth; for if Logic is swamped

by being identified with the whole range of special sciences, it is

killed by being emptied of all adaptation to living intelligence. What

is called Formal Logic _par excellence_ in all its shapes, whether

antiquated as in Hamilton’s or Thomson’s Formal Laws of Thought,

or freshly worked out on a symbolic basis as by Boole and others,

has, it appears to me, this initial defect, _when considered as a

general theory of Logic_. As a contribution to such a theory, every

method which will work undoubtedly has its place, and indicates and

depends upon some characteristic of real thought. But in the central

theory itself, and especially in so short an account of it as must

be attempted in these lectures, I should be inclined to condemn all

attempts to employ symbols for anything more than the most passing

illustration of points in logical processes. All such attempts, I must

maintain, share with the old-fashioned laws of Identity, Contradiction,

and Excluded Middle the initial fallacy of representing a judgment

by something which is not and cannot be in any way an adequate

symbol of one. If, in order to get at the pure form of Knowledge,

we restrict ourselves to very abstract characteristics in which all

knowledge appears, very roughly speaking, to agree, and which can be

symbolized for working purposes by combinations of signs which have

not the essential properties of ideal contents, then we have _ab

initio_ substituted for the judgment something which is a very {50}

abstract corollary from the nature of judgment, and may or not for

certain purposes and within certain limits be a fair representative

of it. We cannot and must not exclude from the form of Knowledge its

modifications according to “matter,” and its nature as existing only in

“matter.”

In fact, the peculiar “form” of _everything_ depends in some degree

on its “matter.” A statue in marble is a little differently treated

if it is copied in bronze. A knife is properly made of steel; you

can only make a bad one of iron, or copper, or flint, and you cannot

make one at all of wax. Different matters will more or less take the

same form, but only within certain limits. So it is in Knowledge. The

_nature of objects as Knowledge_--for we _must_ remember that “form”

in our sense is not something put into the “matter,” something alien

or indifferent to it, but is simply its own inmost character revealed

by the structural relations in which it is found capable of standing

[1]--depends on the way in which their parts are connected together.

[1] The example of the marble statue may seem to contradict

this idea; and no doubt the indifference of matter to form is

a question of degree. But the feeling for material is a most

important element in fine art; and in knowledge there is only a

relative distinction between formal and material relations.

Let us compare, for example, the use of number in understanding objects

of different kinds.

Suppose there are four books in a heap on the table. This heap of

books is the object. We desire to conceive it as a whole consisting

of parts. In order to do so we simply _count_ them “one, two, three,

_four_ books.” If one is taken away, there is one less to count; if

one is added, there is one more. But the books themselves, as books,

are not {51} altered by taking away one from them or adding one to

them. They are parts indifferent to each other, forming a heap which is

sufficiently analysed or synthesised by counting its parts.

But now instead of four books in a heap, let us think of the four

sides of a square. Of course we _can_ count them, as we counted the

books; but we have not conceived the nature of the square by counting

its sides. That does not distinguish it from four straight lines drawn

anyhow in space. In order to appreciate what a square is, we must

consider that the sides are _equal_ straight lines, put together in a

particular way so as to make a figure with four right angles; we must

distinguish it from a figure with four equal sides, but its angles not

right angles, and from a four-sided figure with right angles, but with

only its opposite sides equal; and note that if we shorten up one side

into nothing, the square becomes a triangle, with altogether different

properties from those of a square; if we put in another side it becomes

a pentagon, and so on.

These two things, the heap of books and the square, are _prima

facie_ objects of perception. We commonly speak of a diagram on a

blackboard or in a book as “a square” if we have reason to take it

as approximately exact, and as intended for a square. But on looking

closer, we soon see that the “matter,” or individual attributes, of

each of these objects of our apprehension demands a different form of

knowledge from that necessary to the other. The judgment “_This_ heap

of books has four books in it” is a judgment of enumerative perception.

The judgment “_The_ square has four sides” is a judgment of systematic

necessity.

{52} Why did we not keep the two judgments in the same logical shape?

Why did we say “_This_ heap” and “_The_ square”? Why did we not say

“this” in both propositions, or “the” in both propositions? Because

the different “matter” demands this difference of form. Let us try.

“The heap of books has four books in it.” Probably we interpret this

proposition to mean just the same as if we had said “This heap.” That

is owing to the fact that the judgment naturally occurs to us in its

right form. But if we interpret “The heap” on the analogy of our

interpretation of “The square,” our judgment will have become false.

It will have come to mean “Every heap of books has four books in it,”

and a judgment of perception will not bear this enlargement. The

subject is composite, and one, the most essential of its elements, is

destroyed by the change from “this” to “the.”

Let us try again. Let us say “This square has four sides.” That is

not exactly false, but it is ridiculous. Every square must have four

sides, and by saying “this square” we strongly imply that foursidedness

is a relation of which we are aware chiefly, if not exclusively, in

the object attended to in the moment of judging, simply through the

apprehension of that moment. By this implication the form of the

judgment abandons and all but denies the character of systematic

necessity which its content naturally demands. It is like saying, “It

appears to me that in the present instance two and two make four.” The

number of sides in a square, then, is not a mere fact of perception,

while the number of books in a heap is such a fact.

But you may answer by suggesting the case that an {53} uninstructed

person--say a child, with a square figure before him, and having heard

the name square applied to figures generally resembling that figure,

may simply observe the number of sides, without knowing any of the

geometrical properties connected with it; will he not then be right in

saying, “This square has four sides”?

Certainly not. In that case he has no right to call it a square.

It would only be a name he had picked up without knowing what it

meant. All he has the right to say would be, “This object” or “This

figure has four sides.” That would be a consistent judgment of mere

perception, true as far as it went. It is always possible to apprehend

the more complex objects of knowledge in the simpler forms; but then

they are not apprehended adequately, not _as_ complex objects. It is

also possible to apply very complex forms of knowledge to very simple

objects. Most truths that can be laid down quite in the abstract about

a human mind could also be applied in some sense or other to any speck

of protoplasm, or to any pebble on the seashore. And every simple

form of knowledge is always being pushed on, by its own defects and

inconsistencies, in the direction of more complex forms.

So far I have been trying to show that objects are capable of being

different in their nature as knowledge as well as in their individual

properties; and that their different natures as knowledge depend on the

way in which their parts are connected together. We took two objects

of knowledge, and found that the mode of connection between the parts

required two quite different kinds of judgment to express them. Let us

look at the reason of this.

{54} _The relation of Part and Whole_

3. The relation of Part and Whole is a form of the relation of Identity

and Difference. Every Judgment expresses the unity of some parts in a

whole, or of some differences in an Identity. This is the meaning of

“construction” in knowledge. We saw that knowledge exists in judgment

as a construction (taking this to include maintenance) of reality.

The expression whole and parts may be used in a strict or in a lax

sense.

In a strict sense it means a whole of quantity, that is, a whole

considered as made up by the addition of parts of the same kind, as a

foot is made up of twelve inches. In this sense the whole is the sum of

the parts. And even in this sense the whole is represented within every

part by an identity of quality that runs through them all. Otherwise

there would be nothing to earmark them as belonging to the particular

whole or kind of whole in question. Parts of length make up a whole

of length, parts of weight a whole of weight, parts of intensity a

whole of intensity, in so far as a whole of intensity is quantitative,

which is not a perfectly easy question. Wholes like these are “_Sums_”

or “_Totals_”. The relation of whole to part in this sense is a very

simple case of the relation of differences in an identity, but for

that very reason is not the easiest case to appreciate. The relation

is so simple that it is apt to pass unnoticed, and in dealing with

numerical computation we are apt to forget that in application to any

concrete problem the numbers must be numbers of something having a

common quality, and that the nature of this something may affect the

result as related to real fact, though not as a conclusion from pure

{55} numerical premisses. In a whole of pure number the indifference

of parts to whole reaches its maximum. The unit remains absolutely the

same, into whatever total of addition it may enter.

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