CHAPTER IV

DIMENSIONALITY

Arbitrary Character of Dimensionality--Various Definitions of

Dimension--Real Space and Geometric Space Differentiated--The

Finity of Space--Difference Between the Purely Formal and the

Actual--Space as Dynamic Appearance--The _A Priori_ and the _A

Posteriori_ as Defined by PAUL CARUS.

In previous chapters we have traced the growth and development of the

non-Euclidean geometry showing that the so-called fourth dimension is

an aspect thereof. It is now deemed fitting that we should enter into

a more detailed study of the question of dimensionality with a view to

examining some of the difficulties which encompass it.

The question of dimension is as old as geometry itself. Without it

geometric conclusions are void and meaningless. Yet the conception

of dimensionality itself is purely conventional. In its application

to space there is involved a great deal of confusion because of the

inferential character of its definition. For instance, commonly we

measure a body in space and arbitrarily assign three elements to

determine its position. The simplest standard for this purpose is the

cube having three of its edges terminating at one of its corners.

D

+

A |

\ |

\ |

\ |

\ |

\|

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

B C

FIG. 6.

Thus because it is found that the entire volume of a cube is actually

comprehended within the directions indicated by the lines _ab_, _bc_

and _db_ it is determined that the three coördinates of the point _b_

are necessary and sufficient to establish the dimensions of the cube

and consequently of the space in which it rests. The conception may be

stated in this way: If a collection of elements, say points or lines,

be of such a nature or order that it is sufficient to know a certain

definite number of facts about it in order to be able to distinguish

every one of the elements from all the others, then the assemblage or

collection of elements is said to be of the same number of dimensions

as there are elements necessary to its determination. In the above

figure there are three elements, namely, the lines _ab_, _bc_, and

_db_, which are necessary and sufficient for the determination of the

position of the point _b_. In this way geometers have determined that

our space is tridimensional; but it is obvious that this conclusion is

based not upon any examination of space itself but upon the measurement

of bodies in space. Upon this view it is seen that conclusions based

upon such a procedure render our notion of the extension of bodies

in space identical with the notion of spatial extensity. In other

words, we take bodies in space and by examining their characteristics

and properties arrive at an alleged apodeictic judgment of space. It

is by means of this conventional norm of geometric knowledge that

various other spaces, notably the one-, two-, four-and _n_-space, have

been devised. It would appear that if some more absolute standard of

measurement or definition of space were adopted the confusion which

now clings to the conception of dimension could be obviated. For if it

be true that three and only three elements are necessary to determine

a point-position in our space and that in this determination we also

find the number of dimensions of space, then it may also be true that

_n_-coördinates would just as truly determine the dimensionality of

an _n_-space, which is granted. But then the _n_-space would be just

as legitimate as the three-space; for it is determined by exactly

the same standards. It is both quantitatively and qualitatively the

same. If, however, on account of the exigencies that might arise,

we are forced to seek solace in the notion of an _n_-space whither

shall we turn for it? It cannot be found; for it is imperceptible,

uninhabitable, non-existent, and therefore, absolutely and purely an

abstraction. Consequently, there must be something radically wrong with

the definition of space or with its determinants.

The purely arbitrary character of dimensionality is very aptly

described by CASSIUS JACKSON KEYSER, who says:

"... The dimensionality of a given space is not unique, but

depends upon the choice of the geometric entity for primary or

generating element. A space being given, its dimensionality

is not therewith determined, but depends upon the will of the

investigator who by a proper choice of generating element endows

the space with any dimensionality he pleases. That fact is of

cardinal significance for science and philosophy."[11]

[11] Vide _Monist_, Vol. XVI, 1896, Mathematical

Emancipations.

It is a fact of "cardinal significance" for science; because it

emphasizes the necessity for some more rational procedure than that

of the geometrician in arriving at an absolutely unique method of

determining the dimension and essential nature of real space. Its

significance for philosophy lies in the need of a logical, rigidly

exclusive and absolutely peculiar standard of space definition. The

definition of perceptual space should be such as rigorously inhibits

its inclusion as a particular in any general class. The necessity for

this is warranted by its universality and uniqueness.

The lines of demarkation between what is recognized as perceptual

space and what has been called geometric or conceptual space should

be very sharply drawn. So that when reference is made to either there

will be no doubt as to which is meant. And then, too, conceptual

space is no space at all, properly speaking. It is merely a system of

space-measurement. And as such has no logical right to be put in the

same category as perceptual space.

Real space is unique. Geometric space belongs to a class whose members

are capable of indefinite multiplication. It is certainly most

illogical to identify them. Perceptual space, figuratively speaking,

is a quantity; analytic space is the foot-rule, the yard-stick, the

kilometer, by which it is measured and apportioned. It is logically

impossible to predicate the same conclusion for both of them. That

is, to do so causes a profound fracture of the fundamental norms of

logic. Such conclusions being thus illegitimate it is rather surprising

that an error of this nature should have been made. It is perhaps

accountable for on the grounds of the geometer's complete _insouciance_

as to how his postulates shall stand in their relation to things in the

phenomenal world.

It is agreed that as convenient as is Euclid's system of

space-measurement it is not by any means congruent with the extension

of real space objects. It does, however, approximate congruity with

these objects as nearly as possible. How then could it be expected

that a system of space-measurement so far removed from this primary

congruence as the non-Euclidean system is should exhibit more obvious

signs of correspondence? But the advocates of the _n_-dimensionality

of space have illatively asserted the identity of space and its

dimensions. Accordingly, there is not recognized any distinction

between their conception of space itself and its qualitative

peculiarities. They use the terms interchangeably. So that dimension

means space and _vice versa_. In this lack of discrimination may

be found the source of much of the confusion which attaches to the

conception of space.

If it were arguable that the relation between space and its dimensions

is the same as that between matter and its properties then the

restriction of this relation to three and only three directions of

extent would be disallowed; for the reason that if, as is commonly

done, dimension be made to mean direction of extent, there would

be an unlimited number of directions of extent and they would

all be perceptible. But this is really another fundamental fault.

Non-Euclideans have stretched the meaning of the term dimension so that

it not only includes the idea of direction but an entirely new class of

qualities--the fourth dimension. And despite this reformation of the

original conception, they demand that it shall be called space.

We have just shown that the generic concept of dimensionality is that

three and only three coördinates are necessary and sufficient for

its determination. Granting that this is true, are we not compelled

consequently to see that we have, by adding a fourth or _n_-dimensions,

involved ourselves into a more complex situation than before? For by

postulating a fourth dimension either we have created a new world whose

dimensions are four in number or we have explicitly admitted that the

three dimensions have a fourth. Aside from the logical difficulties

which beset these conclusions there is also set up a condition which is

at variance with the most elementary requirements of common sense.

Thus far mathematical thought has not served to clarify our notions

of space nor to shed any new light upon the vital processes which are

alleged to have their explanation in the new discovery. Simply stated,

metageometricians have brought us to the place where we must either

recognize that the fourth dimension is another sphere lying dangerously

near the earth in which space extends in four primary directions and

in which four coördinates are necessary for its determination or we

are driven to the other horn of the dilemma where we are brought face

to face with the conclusion that the three perceptual space dimensions

have in common a hitherto unknown property or extension in virtue of

which it may be viewed as having an unlimited number of dimensions.

To accept the latter view is equivalent to saying that, in the above

figure, the three lines _ab_, _bc_ and _db_ have formed a triple

_entente_ by which they have mutually and severally acquired a new

domain, hyperspace, and in which, because of the vast resources of the

region, they are able to perform wondrous things.

Let us examine briefly the various current definitions of dimension.

It is assumed by not a few that dimension is the same as _direction_.

But can we grant this wholly to be true? If so, then a mere child

may see that there are and must necessarily be as many dimensions as

there are directions. Primarily, there are six directions of space

and an unlimited number of subsidiary directions. On this view it

is not necessary to invent a new domain of space if the object be

merely to discover and utilize a greater number of dimensions than has

heretofore been allowed. For the identification of the term dimension

with direction already makes available an almost infinite number of

dimensions. But this view is objected to by the advocates, for it is

contrary to the hypothesis of _n_-dimensionality.

Dimension also means _extent_. This is partially true. It cannot be

wholly true. For, if it were, then, space would have only one dimension

which is also not allowable under the hypothesis. Then the definition

leaves out of account the idea that space is at the same time a

direction or collection of directions. The term extension is generic

and when applied to space means extension in all possible directions

and not in any one direction. So that it is not permissible to say

that space extends in this direction or that because it extends in all

directions simultaneously and equally.

Geometers claim that space is a system of coördinates necessary for

the establishment of a point-position in it. This view, however,

identifies space with a system of space-measurement and is therefore

faulty. According to this view there may be as many spaces as there are

systems of space-measurement and the latter may be limitless. But if

the totality of spaces are to be viewed as one space then we shall have

one space with an indefinite number of dimensions; also an indefinite

number of space measurements which would be confusing. Much, if not

all, of such a system's utility and convenience would be unavailable

or useless. That, too, would be in violation of the avowed purpose of

these investigations which is to enhance the utility and convenience of

mathematic operations.

Now it is evident that space is neither direction, extension, a system

of space-measurement nor a system of manifolds whose dimensions are

generable. And this is so for the same reason that a piece of cloth

is not the elements of measurement--inches, feet, yards--by which it

is apportioned. And because we find that the fabric of space lends

itself accommodatingly to our conventional norms of measurement is not

sufficient reason for identifying it with these norms. Here we have the

source of all error in mathematical conclusions about the nature of

space; because all such conclusions are based not upon the intrinsic

nature of space, but upon artificial forms which we choose to impose

upon it for our own convenience. But it should be remembered that the

irregularities which we note are not in space itself but inhere in

the forms which we use. For these purposes space is extremely elastic

and accommodates itself to the shape and scope of any construction

we may decide to try upon it. In this respect it is like water which

has no regard for the shape, size or kind of vessel into which it may

be posited. There is one thing certain that judging from the above

considerations there has been not yet any absolute, all-satisfying

definition devised for space by mathematicians.

The best definitions hitherto constructed are purely artificial and

arbitrary determinations. It is rather anomalous that there should be

so little unanimity about what is the most fundamental consideration

of mathematical conclusions which are supposed to be so certain, so

necessary and universal as to be incontrovertible. Confessedly, it

is a condition which raises again the question as to just what are

the limits of mathematical certainty and necessity and just how far

we shall depend upon the validity of mathematics to determine for us

absolutely certain conclusions about the nature of space. In view

of the uncertainty noted, are we justified in following too closely

the mathematic lead even in matters of logic, to say nothing of our

conception of space? It seems that we shall have necessarily, on

account of the recognized limitations of mathematics in this matter,

to turn to some more tenable source for the norms of our knowledge

concerning space. For in the light of the rather indefensible position

which metageometricians have involved themselves there appears to be no

hope in this direction.

It is undoubtedly safer not to rely altogether upon the purely

abstract, even in the world of mathesis, for any absolute criterion

of knowledge. It is perhaps well that we should expunge the word

_absolute_ from our vocabularies. It is really a misnomer and has no

meaning in the lexicon of nature. There is in reality no _absolute_ in

the sense of final absolution from all conditions or restrictions.

In the ultimate analysis there is unquestionably no hue, tone, quality,

condition nor any imaginable posture of life, being or manifestation

that is absolved from every other one of its class or from the

totality. All these are relational and interdependent. There is no room

for the absolute. In fact, it is a quality which cannot in any way

be ascribed to any aspect of kosmic manifestation. It has existence

only in the mind and has been devised for the purpose of marking the

limits of its scope. All being is relative; all life is relative and is

destined to change its qualities as it evolves. All knowledge is also

relative and what is true of one state may not be true of another; what

is true of one life may not be true of another life; the limitations

of one degree of knowledge may not have any bearings upon another

degree. The norms of one will not satisfy the conditions of another

stage of manifestation. It is always within limits that the criterion

of knowledge will be found to satisfy a given set of conditions. Hence

within certain limits mathematical conclusions will maintain their

validity. Error is committed by pushing the validity of these limits

to a position without the sphere of limitations. This seems to be the

crux of the whole matter. Mathematicians, notably non-Euclideans,

have sought to extend the comparatively small sphere of limits of

congruence between mathematic and perceptual space to such an extent

as to cause it to encroach upon forbidden territory. In doing this they

have erred grievously, causing serious offense to the more sensitive

spirit of the high-caste mathematicians among whom are none more truly

conservative than PAUL CARUS,[12] who says:

"Metageometricians are a hot-headed race and display sometimes all

the characteristics of sectarian fanatics. To them it is quite

clear there may be two straight lines through one and the same

point which do not coincide and yet are both parallel to a third

line."

[12] Vide _Monist_, Vol. XIX, p. 402 (1909).

To the student who has carefully followed the development of the

non-Euclidean geometry and the notion of hyperspace the above

characterization is none too severe nor ill-deserved. Nothing could

more vividly yet correctly portray the impious tactics of the

metageometrician and establish his perceptual obliquity more surely

than the mere fact, mentioned by CARUS, that he can with evident lack

of mental perturbation proclaim that two straight lines, noncoincident

with each other, may pass through a point and yet be parallel to

a third line. But this is a mere trifle, a bagatelle, to the many

other infractions of which he is guilty. The wonder is that he is

able to secure such obsequious acceptance of his offerings as many

of the most serious minded mathematicians are inclined to give. Is

it to be wondered at that, despite the profuse protestations of the

advocates, many who take up the study of the question of hyperspace

should experience a deep revulsion from the posture assumed by

metageometricians with respect to these queries?

Linked with the idea of dimensionality is the notion that space is

infinite. This is a conception which has its roots imbedded in the

depths of antiquity. Primitive man, looking up into the heavens at

what appeared to him as a never ending extension, was awed by its

vastness; but the minds of the most learned of the present-day men

are not free from this innate dread of infinity. It permeates the

thought life of all alike and none seems to be able to rise above it.

Mathematicians, philosophers, scientists all share in the general

belief that space is without limit, unending in extent and eternally

existent. RIEMANN, whose thought life found its most convenient mode of

expression by means of pure mathematics, was the first in the history

of human thought to surmise that space is not infinite but limited

even though unbounded. But his conception has been much vitiated on

account of its entanglement with an _idealized_ construction by which

space is regarded as a thing to be manipulated and generated by act

of thought. Were it not for this his conception would indeed mark

the beginning of a new era in psychogenesis. As it is, when all the

nonsensical effusions have been cleared away from our space conceptions

and men come really to understand something of the essential nature

of space this new era will find its true beginnings in the mind of

RIEMANN. Although it must be said, as is the case with all progressive

movements, the later development of a rationale for this conclusion

will vary greatly from his original conception. For he had in mind a

space that is generable and therefore a logical construction while

ultimately the mind will swing back to a consideration of real space.

Already men are beginning to see a new light. Already they are

beginning to take a new view of space in general. The departure is

especially noticeable in the attitude assumed by HIRAM M. STANLEY.[13]

He says:

"If we seek the most satisfactory understanding of space we shall

look neither to mathematics nor Psychology but to Physics. The

trend of Physics, say with such a representative as OSTWALD, is

to make things the expression of force; the constitution and

appearance of things are determined by dynamism; and we may best

interpret space as a mode of this dynamic appearance."

Space, as a mode of dynamic appearance is a slight improvement upon the

old idea of a pure vacuity; for in the light of what we now know about

space content much of the dignity of that view has been lost. Men now

know that space is not an empty void. They know that the atmosphere

fills a great deal of space. They also have extended their conception

in this direction to include the ether and occultism goes further

and postulates four kinds of ether--the chemical, life, light and

psychographic ethers. But it does not stop here. It postulates a series

of grades of finer matter than the physical which fills space and

permeates its entire extent even to identification with its essential

nature.

[13] _Philosophical Review_, Vol. VII (1898).

STANLEY continues:

"Everything does not, as commonly conceived, fall into some

pre-existent space convenient for it; but everything makes its

own spaciousness by its own defensive and offensive force, and the

totality of all appearance is space in general."

According to STANLEY, not only do physical, perceptual objects, by

their "offensive and defensive force" make their own space but the

appearance of that in which no physical object is makes room for itself

by its own dynamic force. In other words, that which we call "pure

extensity" is by virtue of its dynamism the cause of its own existence.

At first hand there appears to be little worthy of serious

consideration in this view of STANLEY; yet, if carried to its logical

conclusion, the merit of the hypothesis becomes apparent. Accordingly,

interstellar distances which are commonly said to be even without air

or life of any kind are really an appearance possessed of a dynamism

peculiar to itself. And this very force-appearance, constituting

space, is that which makes it perceivable. For instance, let us say

the space that exists between the earth and the moon, is not really

empty nor does it have an existence prior to itself, but is a mode of

dynamic appearance which is the cause of its own existence. Its dynamic

character makes it to appear perceptible to our senses. Logically, if

the dynamism were removed there would remain neither space nor the

appearance of space. If this were true, and it is worthy of serious

thought, then space is certainly finite, as in its totality, according

to STANLEY'S view, it would have to be regarded as a "phenomenon of the

inner and finite life of the infinite."

It is believed that we may go a step further and unqualifiedly assert

that _space is finite_, even denying its infinity as a "general mode

of the activity of the whole." Yet it is transfinite in the sense

that it transcends the comprehension of finite minds or processes. It

is _finite_ because it is in _manifestation_. Everything that is in

manifestation is finite. The infinite is not in manifestation. Infinity

has to be limited always to become manifest. The Deity has limited His

being in order that there may be a manifested universe. All things,

all appearances are finite; because they are phenomena connected with

manifestation.

This question may be viewed from another standpoint. All things in

manifestation or existence are polar in their constitution. For

instance: there cannot be a "here" without a "there." There cannot

be an "upper" without a "lower." Right is copolar with wrong;

good is copolar with evil; night with day; manifestation with

non-manifestation; truth with falsity; infinity with finity and so

on, throughout the whole gamut of the pairs of opposites. What is the

logical inference? Space is paired with a lack of space. There cannot

be what we call _space_ without there being at the same time the

possibility, at least, of the _lack of space or spacelessness_. This is

a conclusion that is rigorously logical and incontrovertible.

But it has been urged that it is impossible for the mind to imagine

a condition where there is no space. It even has been asserted that

it is contrary to the constitution of the mind itself to imagine "no

space." But whether imaginable or not has no effect whatever upon the

validity of the conception. Neither, it is said, can we imagine a

fourth dimension but the mind has come dangerously near to imagining

it. The distance from excogitating upon, discussing and describing

the properties of four-space to imagining it is not so great after

all. Truly it is difficult indeed, it seems, to be able to describe a

thing yet not be able to imagine or make a mental image of it. There

is an evident fallacy here. Either the description of four-space is

no description at all or it is a true delineation of an idealized

construction which is well within the mind's powers of imagination.

Indeed the question of imaginability is not determinative in itself;

for what the mind may now be unable to imagine, because of its more or

less nebulous character, and owing to its infancy may in the course of

time be easily accomplished.

The universe is a compacted _plenum_. It is chock-full of mind, of

life, of energy and matter. These four are basically one. They exist,

of course, in varying degrees of tenuity and intensity and answer to a

wide range of vibrations. Together, in their manifestation of action

and interaction, in their _dynamic appearance_, if you please, they

constitute space. If these were removed with all that their existence

implies there would result a condition of spacelessness in which no

one of the appearances which we now perceive would be possible. Even

sheer extensity would be non-existent. All scope of motility would be

lacking. Dimension, coördinates, direction, space-relations--all would

be impossible.

A straight line is an ideal construction of the mind. It does not exist

in nature. It can never be actualized in the phenomenal universe.

Between the ideal and the real, or actual, there is a kosmic chasm. It

broadens or narrows according as the phenomenal appearance approaches

or recedes from the ideal. What, therefore, can be postulated of

the one will not apply with equal force to the other. They are not

congruent and can never be in the actualized universe. The moment the

actual becomes identified with the ideal it ceases to be the actual.

The universe does not exist as _pure form_, neither does space.

As purely formal constructions of the intellect these can have no

perceptible existence. The phenomenal or sensible may not be judged by

exactly the same standard as the formal. The phenomenal or sensible

represents things as they appear to the senses, or, so far as the

actualized universe is concerned, _as they really are_. The _formal_

represents things as they are made to appear by the mind. It cannot

be actualized. It may be said that the purely formal is the limit of

evolution. The phenomenal may approach the ideal as a limit, but can

never become fully congruent with it. _The difference between the ideal

and the actual is a dynamic one_; it is by virtue of this difference

that the universe is held in manifestation. Evolution is the decrement

of this difference between the purely formal and the actual. So long

then as a kosmic differential is maintained the phenomenal continues

to be manifest: when it is finally reduced to nothing it goes out of

manifestation. The phenomenal is finite; the ideal infinite.

Wherefore, it is undoubtedly improper to refer to space as being

infinite. The term really is inapplicable. Transfinity is much better

and more accurate. Space is transfinite because its scope is greater

than any finite scope of motility can encompass, because it exceeds

finite comprehensibility.

RIEMANN'S notion that space is limited gains weight in the light of the

foregoing considerations. But he could not conceive of the limitability

and unboundedness of space as such in its pure essence; but was

compelled, by his own limitations, to make an idealized construction in

which he could actualize his conception. And for real, dynamic space,

he substituted his ideal construction and proceeded upon that basis.

And of course, his view while it had no reference to perceptual space

nevertheless possessed an illative relation thereto and should be

recognized as construable in that light.

The process of squaring the circle recognized as a geometric

impossibility is significant of the fluxional nature of the universal

residuum perpetually maintained between the archetypal and the

manifested kosmos. It seems that there is a profound truth embodied in

this problem. There is a lesson that may be learned by mathematicians,

philosophers, scientists and thinkers in general. There is an element

of eternal necessity and universality about it which is truly symbolic

of the finity of the universe and the infinity of the archetypal. Just

as a square or a series of polygonal figures inscribed in a circle

cannot be made to coincide exactly with the circle so cannot the actual

be made to coincide with the ideal. The circumference of the circle

is the unapproachable limit of inscribed squares. If it were possible

so to multiply squares thus inscribed that a figure coincident with

the circumference of a circle might be constructed, such a figure

would not be a square but a circle. The manifested universe is like

that--the process of inscribing squares within a circle. It is ever

_becoming_, _evolving_, _developing_, but never quite attains. Infinity

is a process. But no single stage in that process is infinite. Each

is finite and their totality makes the infinity of the process. The

universe manifested to the senses or the intellect is finite.

"Space," says PAUL CARUS, "is the possibility of motion in all

directions."[14] To be sure, it is admitted that space offers

opportunity for motion in all directions. But is space this opportunity

of motility? Or is possibility of motion space? The possibility of

motion must rest in the thing that moves. It implies a potency in the

moving entity, not in space. If it is meant that space is the potency

that resides in the moving element it is still more difficult to

understand the connotation. But even granting this view, are we not

compelled to recognize the dynamism of space as a necessary inference?

Another definition which CARUS gives is that space is a "_pure form of

extension_." If it be granted that space is a pure form of extension

we should have to conclude that it has no actual existence; for _pure

form_ does not exist except as an idealized construction. It cannot

be found in nature. Pure form is _ideal_. Impure or natural form is

actual. Therefore the space in which we live and in which the universe

exists cannot be a "pure form" because life cannot exist in the purely

formal. It is useless to talk about space as mere form so long as

it maintains life. The difficulty which this phase of the question

presents is another evidence of the inadequacy of our definitions.

[14] Vide _Foundations of Mathematics_, p. 107.

It is also found to be impossible to concur in CARUS' conception of

knowledge _a priori_. His notion of the _a priori_ varies somewhat from

the Kantian view. He defines it as an "idealized construction," the

"mind made," "abstract thought," and places it in the same category as

a concept. This is undoubtedly born of his desire to get rid of KANT'S

"innate ideas" which seem to be distasteful to him. But in doing so it

appears that the real _a priori_ has been overlooked. Let us examine

for a moment this important question. The _a posteriori_ connotates all

knowledge gained through the senses, or sense experience. All knowledge

therefore whose origin can be traced to the senses is knowledge _a

posteriori_. Now, knowledge _a priori_ should be just the opposite of

this. It should indicate such knowledge as that which does not have

its origin in the senses, or which is not dependent upon the ordinary

avenues of sense-experience. Abstract thought is as truly experience as

smelling, seeing or hearing. It is by traversing its scope of motility

that the mind finds out what the norms of logic are. It could not

remain quiescent and discover them. It has to be active, examining,

comparing and judging. Almost the entire range of thought, its entire

scope, is characterized by the _a posterioristic method_. In fact,

all thought is _a posterioristic_. Despite the fact that, in thinking

in the abstract, it is necessary mentally to remove all elements of

concreteness, all materiality and all actuality, the conclusions

reached have to be referred to the standards maintained by the actual,

the concrete and the material. Then we do not start with the abstract

in our thinking. We begin with the concrete and by mentally removing

all physical qualities arrive at the abstract.

The mind has a constitution. It acts in a given way because it is its

nature so to act. Not because it has learned to act in that manner. It

performs certain functions intuitively without previous instruction

or experience for the same reason that water dampens or heat warms.

It is natural for it to do so. This naturalness, this performance of

function without being taught or without experience constitute the

principle of _apriority_ in the mind. _Aprioriness_ is a principle

of mind partaking of the very nature and essence of mind. It is the

very mainspring of mentality. Perception and conception are processes

which the mind performs intuitively. The mind perceives and conceives

because it is impossible for the normal mind to do otherwise. We take

a view upon a given question; we assume certain mental attitudes of

affirmation, negation or indifference because we have learned to do so

by virtue of the tuitional capability of mind. These describe the _a

posteriori_. That is, all knowledge obtained as a result of voluntary

mental processes constitutes the mass of knowledge _a posteriori_. The

_a priori_ is what the mind is by nature: the _a posteriori_ is what

the mind becomes. It is the mind-content.

The _a priori_ is not a mental construction; it is an essential

principle of mind. It should not be identified with the "purely

formal," as is done by PAUL CARUS:[15]

[15] Vide _Foundations of Mathematics_, p. 42.

He says:

"The _a priori_ is identical with the purely formal which

originates in our mind by abstraction. When we limit our attention

to the purely relational, dropping all other features out of

sight, we produce a field of abstraction in which we can construct

purely formal combination, such as numbers, or the ideas of types

and species. Thus we create a world of pure thought which has the

advantage of being applicable to any purely formal consideration

and we work out systems of numbers which, when counting, we can

use as standards of reference for our experience in practical

life."

Thus CARUS definitely links up the _a priori_ to a factor which is

nothing more nor less than a mental by-product. For such is the

category in which would be placed both the process of abstraction and

its results. It is therefore exceedingly difficult to understand why

so cursory a consideration should have been given to the principle of

_apriority_ than which no other element of mind is more essentially a

part of the mind itself.

The formal is symbolic. It signifies an informing quantity. Pure form

itself is but a negation of that which formerly filled it. Then, too,

the formal is purely artificial because it is a mental construction.

Essentially there is as much difference between the purely formal and

the _a priori_ as between creator and creature, as between potter and

clay. The one is the builder, the other is the material; the one the

knower and the other the known. Thus, the only reason that the formal

is found to be answerable to the _a priori_ at all is due to the fact

that it is construable only upon the basis of the _a priori_. But

being so is not sufficient warrant for its identification with the _a

priori_. The formal merely represents the totality of possibilities in

the universe as viewed by the mind; but as the number of possibilities

open to the mind is, on account of its nature and purpose limited, it

is not to be supposed that it (the mind) shall measure up to all the

possibilities offered by the formal. Moreover, it is certain that no

sane mind cherishes the hope that there shall ever be found in the

universe of life and form a congruence for all of the possibilities

held out by the purely formal.

As an eternal principle of mind, the _a priori_ is in agreement with

the divine mind of the kosmos. In its _aposteriority_ the mind is of

diverse tendences, qualities and characteristics. Apriorily, it acts in

unison with the eternal purpose of life and the universal mind. In its

aposteriority, it often goes awry. In its _apriority_ it can never be

insane; insanity is a symptom of the morbid _a posteriori_.

The mind in man acts the same as mind in the vegetal and lower animal

kingdoms. Metabolism and katabolism, indeed all cell-activity, are

_a priori_ performances of the mind. Growth and all its phenomena,

the cyclicism of natural processes, and every activity connected

therewith belong to the category of the _a priori_. Cells multiply,

divide, build up and tear down tissues and they do it intuitively. Most

certainly these functions are performed without any assistance from the

intellect. All the myriad activities in nature with which the intellect

in man has not the slightest concern, truly acting in accord with some

primordial impetus, are activities _a priori_.

Now what is the attitude of the intellect, in the light of the _a

priori_, towards space and the question of dimensionality? It is

evident that no matter what this attitude may be it is in agreement

with the constitution of things and of the universe. And if so, it is

right and without illusion. It is also evident that whatever notion

_a posteriori_ the intellect may entertain with respect to these

questions is unavoidably liable to the illusionary drawbacks common to

conclusions based upon limited experience. The geometric view of space

belongs to the category of the _a posteriori_. Hence it is subject to

the usual imposition of error.

Tersely stated, KANT's view of space is that it is a form of intuition,

a form _a priori_, a transcendental form. As such he considered it

to be a native form of perception not belonging to the category of

sense-deliveries. Accordingly, space is a form of intuition arising

out of and inhering in the constitution of mind. It is a notion

which constitutes the universal and eternal prerequisite of mind and

is, therefore, intrinsically necessary to all phases of mentation.

Now, this being true just what may be said to be the relation of

dimensionality to this _a priori_ form of space which is found to

exist in the mind as an eternal aspect of its nature? Does the mind

intuitively measure its contents or its operations by the empirical

standard of space-measurement known as dimension? Is the attitude of

the mind towards the objectively real one of discrimination _a priori_

as to the direction or dimension in which a percept may originate? In

other words, does the mind habitually and intuitively refer its data

to a system of coördinates for final determination? There is no other

answer but that the mind makes no such reference and is dependent upon

no kind of coördinate system in any of its operations _a priori_. As a

form of intuition, the space notion is present in the mind as a scope

of existence, of motility, of being and of sheer roominess. The notion

of direction or dimension, being an artificial construction, does not

enter into this form of intuition at all. It is only when the mind

comes to elaborate upon its perceptive performances and possibilities

that the questions of relations, positions and directions arise.

But this latter is a matter separate and distinct from the state of

awareness which embodies the notion of space.

Dimension is an arbitrary norm constructed by the mind for the

determination of various positions in space. It is an accident or

by-product of the process of elaborative cognition, a convenient

and appropriate means of measurement for objects in space and their

space-relations. But it is no more _a priori_ than a foot rule or a

square. But being purely an empirical product it may be said to be

an aspect of psychogenesis because it relates to the evolutionary

aspect of mind. The assumption may therefore be allowed that the

mind may, in the course of its evolution, find it convenient and

appropriate to devise an additional ordinate or dimension to satisfy

the necessities of its more complex ramifications into the nature of

things and to determine their greatly increased space-relations. It

may be even possible for the mind to function normally in a space of

four dimensions. But this would simply be a new adjustment, not a

change in the essential nature of mind. It would be like the series of

adjustments to environments which man has made in the onward movement

of civilization. There has been no serious change in the manhood

_per se_ of man. That has remained the same; there has been merely a

complication of environmental influences. Similarly, in the acquisition

of four-dimensional powers, granting that such an acquisition is

possible, there is nothing to be added to the _aprioriness_ of mind

_itself_. Is it not, therefore, logical to assume that the discovery

of a fourth coördinate and the consequent conceptualization of the

same, point to the development in the mind of a greatly extended

faculty, more keenly penetrative powers of cognition and a further

diversification of its environments than it has hitherto enjoyed?

Indeed, it seems so.

The mystery of space · 第 4 / 11 章