misapprehensions. I shall therefore attempt to elucidate the subject
with reference to the objections presented by Professor Mach.
#Recapitulation.#
The main idea set forth in my article "Feeling and Motion" may be
briefly recapitulated as follows. Our feelings are phenomena which to
an observer who could see all the processes taking place in our brain,
would appear as motions of a special kind. Motions and feelings are two
aspects of one and the same reality. But feeling cannot be explained
as transformed motion. Accordingly, the elements of the conscious
feeling which now exists and now disappears, must have existed before.
The presence of elements of feeling must be an additional feature of
the processes of nature not included in the term motion, and not
observable in motions, yet inseparably bound up in motions. Or, in
other words, feelings and the elements of feeling are the subjective
aspect of what objectively appears as and is called motions.
The term "elements of feeling" employed in this sense has been adopted
from Clifford. The idea that feelings and motions are two aspects of
one and the same reality has been held by several psychologists; among
whom are the founders of the science of psycho-physics, especially
Fechner.
I. MOTION AND FEELING.
Professor Mach says: "Putting together motion and feeling goes as much
against me as would, say, the co-ordination of numbers and colors."
#Justification of juxtaposition.#
The putting together of two concepts depends upon the purpose of our
investigation. Motion and feeling, in spite of their disparity, have
one quality in common which justifies their juxtaposition. Both in
their spheres are terms of the most general circumscription.
#Feeling described.#
By feelings I understand those features of our experience which
constitute what may be called the awareness of the present state.
Feeling comprehends all the many degrees of awareness in pleasures and
pains, sensations and thoughts, emotions and ideals. It constitutes the
subjectivity of our existence and furnishes the basis of all psychic
life. Feeling is the most general term of its kind.
#Motion described.#
By motion I understand all kinds of changes in the objective world
that can either be directly observed or are supposed to be observable.
Indeed all changes taking place must, objectively represented, be
thought of as motions.
Feeling and motion being each the broadest concept of its kind, the
question, In what relation do motions stand to feelings? appears to be
quite legitimate.
* * * * *
Concerning the relation that obtains between feeling and motion,
Professor Mach objects to the use of the expression "feeling
accompanies motion." "Material processes," he says, "are not
accompanied by feeling, but both are the same." And in another passage,
"The parallelism stands to reason, since everything is parallel to
itself."
#The term "accompany" inadequate.#
I grant most willingly that the term "accompany" is inadequate, and I
admit that a certain feeling and a certain motion form one inseparable
process. There is no duality of feeling and motion, both are different
abstractions made from one and the same reality. I do not say that
feeling and motion are identical, not that they are one and the same;
but I do say that they are one. There is no such thing as pure feeling;
real feeling is at the same time motion. Feeling by itself does not
exist in reality. Pure feeling is a mere abstraction. And wherever the
expression parallelism between feeling and motion has been used, it can
mean only a parallelism between the two spheres of abstraction.
Professor Mach continues: "They [motion and feeling] are not two sides
of the same paper (which latter is invested with a metaphysical rôle in
the simile), but simply the _same_ thing."
#Fechner's simile.#
For the same reason Professor Mach objects to Fechner's comparison.
Yet it seems to me that Fechner hit the mark when he compared feeling
and motion to the inside and the outside curves of a circle; they are
entirely different and yet the same. The inside curve is concave,
the outside curve is convex. If we construct rules relating first to
the concave inside and then to the convex outside, we shall notice a
parallelism in the formulas; yet this parallelism will appear only in
the abstractions which have been made of one and the same thing from
different standpoints and serving different purposes. The abstract
conceptions form two parallel systems, but the real thing can be
represented as parallel only in the sense that it is parallel to
itself. If we consider the real thing, it represents a parallelism of
identity. There is but one line, and this one line is concave if viewed
from the inside, it is convex if viewed from the outside.
#The simile of a sheet of paper.#
The simile which I introduced of the two sides of one and the same
sheet of paper was devised to convey no other meaning than this
construction of Fechner's comparison. The paper is invested with
a metaphysical rôle only in the case where the simile is otherwise
construed. There is no page which exists of itself as a mere
mathematical plane independent of the paper of which it forms a side.
Thus there can never be in reality a page without its counterpage.
The paper, its size and color, belong to the page and constitute its
properties.
Thus the abstraction 'feeling' represents my looking at the one side
of reality. I leave, and from the subjective standpoint I have to
leave, the other side out of account. Yet the other side of the sheet
is inseparable from the one at which I am now looking, just as much as
feeling is inseparable from motion. And I am constrained to admit the
truth of the reverse also: motion is inseparable from feeling, but with
the limitation that motions need not be on their subjective side actual
feelings; they may be only elements of feeling which under certain
conditions become actual.
#The metaphysical misinterpretation.#
I am aware that my comparison of feeling and motion to the two sides
of one sheet of paper may be easily misinterpreted. But is not that a
danger to which all comparisons are subject? A comparison is always
imperfect, or as the Romans used to say, it limps: "Omne simile
claudicat." And is not reality liable to be misinterpreted in the
same way? Have not some philosophers thus introduced the metaphysical
explanation of the unknowableness of things in themselves? Such
philosophers conceive the two sides of a sheet of paper (the abstract
mathematical planes of the pages) as phenomenal and the paper as their
metaphysical essence. The size of the sheet, the color of the paper,
and all its other qualities are in a metaphysical world-conception
represented as properties of which the thing is possessed—not as
constituting the thing, but as essentially different from it.
It appears to me that Professor Mach in spite of his opposition to
Fechner's simile and to the expression that feeling and motion are two
aspects of one and the same reality, entertains the same view. At least
his words: "Only the relation in which we consider them makes them at
one time physical elements, at another time feelings," are to that
effect.
II. SENSATIONS AND THOUGHTS.
#Professor Mach's problem.#
The difference between Professor Mach's view and mine may appear
greater than it is, because the problem which Professor Mach treats in
his article "The Analysis of the Sensations," lies in quite a different
field from that of the problem of the relation of feeling to motion.
The problem being different, the same and similar terms are not only
used for different purposes, but demand also different comparisons.
Professor Mach's symbols _A B C_ ... and α β γ ... represent a contrast
different from that of feeling and motion. They represent the contrast
of sensations and thoughts. Sensations, such as green and hard, are
colors, pressures, tastes, etc; thoughts are memory-images, concepts,
volitions, etc.
Professor Mach says: "How the representative percepts of imagination
and memory are connected with sensations, what relations they bear to
them, as to this I dare venture no opinion.... Monism, as yet, I cannot
thoroughly follow out; because I am lacking in clearness with regard to
the relation of α β γ ... to _A B C_ ...; but I believe that the first
step towards a competent monism lies in the assertion that the same _A
B C_ ... are both physical and psychical elements."
My symbols _A B C_ ... and α β γ ... represent the contrast of physical
and psychical elements, not of sensations and thoughts. Concerning
thoughts, Professor Mach says he is much inclined to co-ordinate them
with sensations so that his Greek symbols might differ from his Italic
symbols not otherwise than the latter, viz. _A B C_ ...; differ among
themselves. Taking this ground, I believe, it would be preferable to
symbolise them accordingly among the Italic letters, perhaps as _X Y
Z_. In the diagrams on page 407 they are called Μμ, Νν, Σς.
#Feeling, sense-impression and sensation defined.#
According to my terminology, feeling, as explained above, is the most
general term expressing any kind and degree of subjective awareness.
A sense-impression is a single irritation of one of the senses,
the irritation being a special kind of motion plus a special and
correspondent kind of feeling. A sensation is a sense-impression that
has by repetition acquired meaning. A later sense-impression, when
felt to be the same in kind as a former sense-impression, constitutes,
be it ever so dimly, an awareness of having to deal with the same
kind of cause of a sense-impression; thus giving meaning to it. By
sensation, accordingly, I understand a sense-impression which has
acquired meaning. And feelings that have acquired meaning, I should
call mental states. Representative feelings (feelings that have a
meaning) are the elements of mind.
#Thought and thinking defined.#
By thinking I understand the interaction that takes place between
representative feelings. Such are the comparisons of sensations
with memory-pictures, or of memory-pictures among themselves, the
experimenting with memory-pictures so as to plan new combinations, etc.
The products of thinking are called thoughts; and by thought in the
narrower sense is commonly understood abstract thought which on earth
is the exclusive privilege of man.
If I am not mistaken Professor Mach understands by sensations
(represented by him as _A B C_ ...) what I should call
sense-impressions; while thoughts, memories, and volitions (represented
by him as α β γ ...) form what I should call mind, or all kinds of
mental states, that is, the domain of representations.
The higher spheres of thought, or representative feelings, grow out
of and upon the lower spheres. Sense-impressions, as I have attempted
to explain in the article "The Origin of Mind" (_The Monist_, No. 1),
are the data which are worked out into concepts and ideas; they are
the basis upon which the whole structure of mind rests. The reflex
motions of simple irritations, being modified in higher spheres by the
rich material of experience consisting of memory-images, and by the
possibility of forethought created through experience, become volitions.
#Monism and the origin of mind.#
A monistic explanation of the rise of mind from elements that are not
mind is possible only on the supposition that the objective processes
of motion are not mere motions but that they are at the same time
elements of feeling.
Is this not the same position as Professor Mach's, where he says that
"the first step towards a competent monism lies in the assertion that
the same _A B C_ ... are both physical and psychical elements"? and
again: "The same _A B C_ ... are both elements of the _world_ (the
'outer'[83] world namely) and elements of feeling."
[83] Professor Mach here says "outer world." I should prefer
to replace it by the expression "objective world," because
the motions of a man's brain belong to the outer world of
all other men. To make sure of including the actions of
my own body in this outer world, I should prefer the term
"objective world," making feelings alone (to the exclusion of
the subject's own motions) the constituents of the subjective
world.
#Agreement with Professor Mach.#
Considering the two last-quoted sentences of Professor Mach, it appears
to me that all differences vanish into verbal misunderstandings. Yet
since I am not at all sure about it, I may be pardoned for becoming
rather too explicit. The adjoined diagram may assist me in making my
ideas clear.
[Illustration: Fig. I. Fig. II.]
#Explanation of the diagrams.#
Let the large circle of both figures represent a sentient being, a man.
The periphery is his skin. The small circle enclosing _K_ and _L_ is a
sensory organ; the other small circle enclosing _M_ and _N_ represents
the hemispheres of his brain. _A_ and _B_ are processes taking place
outside of the skin of this man. _A_ produces an effect in _K_; _B_ in
_L_. The line _R_ represents a reflex motion. _M_ and _N_ are concepts
and abstract ideas derived from such impressions as _K_ and _L_. The
line _S_ represents an act of volition.
All these symbols represent motions in the objective world. We know
through physiological investigations that _K_, _L_, _M_, and _N_ are
motions; in our individual experience they appear as feelings.
The second figure represents in agreement with my system of symbols
the states of awareness, in Greek letters. Certain physiological
processes (_K L R_, _M N S_ of Figure I) appear subjectively as states
of awareness (i. e. κ λ ρ, μ ν ς of Figure II). Yet _A_ and _B_ remain
to the thinking subject mere motions. If they possess also a subjective
side, although only in the shape of potential feeling, it does not and
it cannot appear.
#Sensations not elementary.#
Professor Mach calls green, hard, etc., which in a certain relation
are our sensations, "the elements of the world." These processes
characterised as "green," "hard," etc., are in my opinion too special
and at the same time too complicated to be considered elementary. I
grant that they are elements of mind, because if further analysed, they
cease to be mental phenomena. But they are not elements _per se_, not
elements of the world. It remains doubtful to me whether Professor Mach
understands by his term "sensation" only _K_ κ and _L_ λ or the whole
relations _A K_ κ, and _B L_ λ. Taking it that he represents _A B C_
... as both elements of the world and sensations, it almost appears
certain to me that his term "sensation" stands for the whole process
_A K_ κ, and that he considers the scientific analysis of this process
into _A_ the outside thing, into _K_ the nerve-vibration corresponding
in form to the outside thing, and κ the feeling that takes place in
experiencing the sense-impression _A K_, as an artificial procedure
that serves no other purpose than that of familiarising us with certain
groups of elements and their connections. The processes _A K_ κ, _B L_
λ, in that case would be considered by Professor Mach as the actual
facts, while the _A_ and _B_, the _K_ and _L_, the κ and λ represent
mere abstract representations without real existence, invented by
scientists in order to describe the realities _A K_ κ, _B L_ λ, etc.,
with the greatest exactness as well as economy of thought. In their
separate abstractness they are the tools of science only and we must
not take them for more than they are worth.
#Thoughts as mental implements.#
If this be so, I understand Professor Mach very well and I agree with
him when he looks upon all _M_ and _N_ with their respective μ and ν as
being "noumena, _Gedankendinge_, things of thought." They are mental
tools. Sense-impressions are realities, but mental representations are
implements; they are auxiliaries for dealing with realities; they are
"the augers and saws" employed in the different fields of cognition.
#Persistence of the elements of mind.#
Professor Mach says in his article "The Analysis of the Sensations":
"When _I_ (the ego) cease to perceive the sensation green, when I die,
then the elements no longer occur in their customary, common way of
association. That is all. Only an ideal mental economical unity, not
a real unity, has ceased to exist." The term sensations, it appears
to me, can in this passage be interpreted neither as _K_ κ only, nor
as the whole relations _A K_ κ, but as any _A B C_ ... relations; and
since Professor Mach has not excluded from them the element of feeling,
I should have to represent them by _A_ α, _B_ β, _C_ γ.... Sensations
as I understand the term (viz. _A K_ κ, _B L_ λ), are elements of
mind; if they are further analysed they cease to be mental states.
Says Professor Mach: "If I close my eye (_K_) withdraw my feeling hand
(_L_), _A B C_ ... disappear. In this dependence _A B C_ ... are called
sensations." Should we not rather say, they cease to be sensations, if
this dependence ceases? Accordingly, sensations and sense-impressions
are for this and for other reasons not indecomposable, not ultimate
atoms. The elements of mind can be further analysed into the elements
of the elements of mind. The elements of mind do not persist; but the
ultimate elements of the elements of mind, whatever they are, do (or at
least may) persist.
When speaking of the elements of the elements of mind we cease to deal
with objects of actual experience as much as a physicist or chemist
does who speaks about atoms. Nevertheless the analysis is as legitimate
in our case as it is in the chemist's. If in the above quoted passage
I am allowed to replace Professor Mach's term "sensations" by elements
of sense-impressions, I should not hesitate unreservedly to accept
his idea. These elements of sensations would be all kinds of natural
processes, all kinds of motion. They would be physical actions which
are not mere motions but also and at the same time elements of feeling.
#Ideas as contrivances for comprehension.#
It is true that abstract concepts, and especially scientific terms and
theories, are mere contrivances to understand the connections among,
and the qualities of, real things. Ideas are not the real things, but
their representations, and some ideas are not even representations;
they are solely of an auxiliary nature and comparable to tools. They
are used as working hypotheses wherever the real state of things is in
part hidden from us, until we have found the actual connections. As
soon as the actual connections are found we can and must lay down our
tools.
In a certain sense all words and concepts are tools for dealing with
the realities they represent. But some words are tools in a special
sense. They have been invented for acquiring a proper representation.
#The dignity of mental tools.#
Professor Mach says: "The implement is not of the same dignity or
reality as _A B C_...." It appears to me that these implements (if
they are of the right kind) have almost a higher dignity (although not
reality) than the material to which they are applied. My respect for
tools is very great, for tools are the most important factors, perhaps
the decisive factors, in the evolution of man. The usage of tools
has matured, nay created the human mind, and words,—scientific and
abstract terms and theories not excluded,—are the most important and
most sacred tools of all.
Some ideas, it is true, have to be laid aside like tools that are
no longer wanted; but there are other ideas which we cannot lay
aside, because they have more value than the ideas of a mere working
hypothesis. Some ideas are indispensable and will remain indispensable;
we shall always have to employ them in order to represent in our mind
the connection between certain facts. If we see a train pass into a
tunnel and emerge from it at the other end, we will connect in our mind
these two sensations by the thought of the train's passage from one end
to the other. This idea is not a sensation; it is a noumenon. Shall it
therefore be called a _mere_ noumenon, a tool that has to be discarded
as soon as we are accustomed to expect a train to emerge from the one
end of a tunnel soon after it has disappeared into it at the other end?
#Noumena legitimate, if representing realities.#
There are scientific concepts which, for some reason or other, can
never become objects of direct observation; they can never become
sensations. Nevertheless we must think them together with certain
sensations as indispensable connecting events taking place behind the
stage and hidden from our eyes. Our conception of a train hidden from
sight in a tunnel, it is true, is a noumenon, but it is a legitimate
noumenon, it represents a reality. So also many scientific ideas,
although undoubtedly things of thought, are legitimate noumena. If
they contain and in so far as they do contain nothing but formulated
features of reality or inevitable conclusions from verified and
verifiable experiences, these things of thought represent something
real, which means that if we were in possession of microscopes of
sufficient power, or if we could look behind the veil that hides them
from our sight, we should see them, just as we should see the train if
the rock through which the tunnel leads were transparent.
III. THE ORIGIN OF FEELING.
Concerning the origin of feeling Professor Mach says: "The question how
feeling arises out of the physical element has for me no significance."
I agree that we cannot ask how feeling arises out of the physical
element. But feeling being a fleeting phenomenon, to propose the
problem of the origin of feeling _has_ a significance.
#Physical elements with and without feeling.#
Some physical elements—namely, those of our own body—are indubitably
possessed of the subjective phenomena of feeling. And as to certain
other physical elements, observable in our fellow creatures, that is in
men and animals, no one would think of denying their presence either.
But there are physical elements which we regard as bare of all feeling.
The wind that blows, and the avalanche that plunges into the valley are
not supposed to be feelings. Yet the energy of the wind and the energy
of the avalanche may be utilised and ultimately stored up in food. The
food may be changed into human energy and then the element of feeling
appears as if called forth out of the void. We agree that feeling has
not been changed from motion. But if feeling was not motion before,
what was it? Feeling cannot be a creation from nothing. Consequently
it must in its elements have existed before. Feeling, namely actual
feeling, must be regarded as a special mode of action of the elements
of feeling. If all that which we can observe in motion, all that
which the term motion comprises, constituting the objective changes
taking place in nature, contains nothing of feeling or of the elements
of feeling, we must yet attach to every motion the presence of this
element of feeling.
#Elements of feeling not observable.#
That the potential subjectivity of the physical elements, namely
the elements of feeling, cannot be seen; as motions can be seen and
objectively observed, is not a reason that militates against this view;
for it is the nature of all subjective states to be felt only by the
feeling subject. If all feelings are objectively unobservable except
by their correspondent motions, the elements of feeling can form no
exception to the general rule.
* * * * *
#The animation of all nature.#
Professor Mach says: "Some years ago I should have agreed _in toto_
with the passages in which Dr. Carus speaks of the animation of all
nature and of the feeling that accompanies every motion."
#Nature not all feeling.#