Thus, when the thoughtful man speaks of _real space_, he cannot mean by
the word only the actual and possible relations of arrangement among
the things and the parts of things directly revealed to his sense of
touch. He may speak of real things too small to be thus perceived, and
of their motion as through spaces too small to be perceptible at all.
What limit shall he set to the possible subdivision of _real_ things?
Unless he can find an ultimate reality which cannot in its turn become
the appearance or sign of a further reality, it seems absurd to speak
of a limit at all.
We may, then, say that real space is infinitely divisible. By this
statement we should mean that certain experiences may be represented by
others, and that we may carry on our division in the case of the
latter, when a further subdivision of the former seems out of the
question. But it should not mean that any single experience furnished
us by any sense, or anything that we can represent in the imagination,
is composed of an infinite number of parts.
When we realize this, do we not free ourselves from the difficulties
which seemed to make the motion of a point over a line an impossible
absurdity? The line as revealed in a single experience either of sight
or of touch is not composed of an infinite number of parts. It is
composed of points seen or touched--least experiences of sight or
touch, _minima sensibilia_. These are next to each other, and the
point, in moving, takes them one by one.
But such a single experience is not what we call a line. It is but one
experience of a line. Though the experience is not infinitely
divisible, the line may be. This only means that the visual or tactual
point of the single experience may stand for, may represent, what is
not a mere point but has parts, and is, hence, divisible. Who can set
a limit to such possible substitutions? in other words, who can set a
limit to the divisibility of a _real line_?
It is only when we confuse the single experience with the real line
that we fall into absurdities. What the mathematician tells us about
real points and real lines has no bearing on the constitution of the
single experience and its parts. Thus, when he tells us that between
any two points on a line there are an infinite number of other points,
he only means that we may expand the line indefinitely by the system of
substitutions described above. We do this for ourselves within limits
every time that we approach from a distance a line drawn on a
blackboard. The mathematician has generalized our experience for us,
and that is all he has done. We should try to get at his real meaning,
and not quote him as supporting an absurdity.
[1] "Seeing and Thinking," p. 149.
CHAPTER VII
OF TIME
27. TIME AS NECESSARY, INFINITE, AND INFINITELY DIVISIBLE.--Of course, we
all know something about time; we know it as past, present, and future;
we know it as divisible into parts, all of which are successive; we know
that whatever happens must happen in time. Those who have thought a good
deal about the matter are apt to tell us that time is a necessity of
thought, we cannot but think it; that time is and must be infinite; and
that it is infinitely divisible.
These are the same statements that were made regarding space, and, as
they have to be criticised in just the same way, it is not necessary to
dwell upon them at great length. However, we must not pass them over
altogether.
As to the statement that time is a _necessary_ idea, we may freely admit
that we cannot in thought _annihilate_ time, or _think it away_. It does
not seem to mean anything to attempt such a task. Whatever time may be,
it does not appear to be a something of such a nature that we can
demolish it or clear it away from something else. But is it necessarily
absurd to speak of a system of things--not, of course, a system of things
in which there is change, succession, an earlier and a later, but still a
system of things of some sort--in which there obtain no time relations?
The problem is, to be sure, one of theoretical interest merely, for such
a system of things is not the world we know.
And as for the infinity of time, may we not ask on what ground any one
ventures to assert that time is infinite? No man can say that infinite
time is directly given in his experience. If one does not directly
perceive it to be infinite, must one not seek for some proof of the fact?
The only proof which appears to be offered us is contained in the
statement that we cannot conceive of a time before which there was no
time, nor of a time after which there will be no time; a proof which is
no proof, for written out at length it reads as follows: we cannot
conceive of a time _in the time_ before which there was no time, nor of a
time _in the time_ after which there will be no time. As well say: We
cannot conceive of a number the number before which was no number, nor of
a number the number after which will be no number. Whatever may be said
for the conclusion arrived at, the argument is a very poor one.
When we turn to the consideration of time as infinitely divisible, we
seem to find ourselves confronted with the same difficulties which
presented themselves when we thought of space as infinitely divisible.
Certainly no man was immediately conscious of an infinite number of parts
in the minute which just slipped by. Shall he assert that it did,
nevertheless, contain an infinite number of parts? Then how did it
succeed in passing? how did it even _begin_ to pass away? It is
infinitely divisible, that is, there is no end to the number of parts
into which it may be divided; those parts and parts of parts are all
successive, no two can pass at once, they must all do it in a certain
order, one after the other.
Thus, something must pass _first_. What can it be? If that something
has parts, is divisible, the whole of it cannot pass first. It must
itself pass bit by bit, as must the whole minute; and if it is infinitely
divisible we have precisely the problem that we had at the outset.
Whatever passes first cannot, then, have parts.
Let us assume that it has no parts, and bid it Godspeed! Has the minute
begun? Our minute is, by hypothesis, infinitely divisible; it is
composed of parts, and those parts of other parts, and so on without end.
We cannot by subdivision come to any part which is itself not composed of
smaller parts. The partless thing that passed, then, is no part of the
minute. That is all still waiting at the gate, and no member of its
troop can prove that it has a right to lead the rest. In the same outer
darkness is waiting the point on the line that misbehaved itself in the
last chapter.
28. THE PROBLEM OF PAST, PRESENT, AND FUTURE.--It seems bad enough to
have on our hands a minute which must pass away in successive bits, and
to discover that no bit of it can possibly pass first. But if we follow
with approval the reflections of certain thinkers, we may find ourselves
at such a pass that we would be glad to be able to prove that we may have
on our hands a minute of any sort. Men sometimes are so bold as to
maintain that they know time to be infinite; would it not be well for
them to prove first that they can know time at all?
The trouble is this; as was pointed out long ago by Saint Augustine
(354-430) in his famous "Confessions," [1] the parts of time are
successive, and of the three divisions, past, present, and future, only
one can be regarded as existing: "Those two times, past and future, how
can they be, when the past is not now, and the future is not yet?" The
present is, it seems, the only existent; how long is the present?
"Even a single hour passes in fleeting moments; as much of it as has
taken flight is past, what remains is future. If we can comprehend any
time that is divisible into no parts at all, or perhaps into the minutest
parts of moments, this alone let us call present; yet this speeds so
hurriedly from the future to the past that it does not endure even for a
little space. If it has duration, it is divided into a past and a
future; but the present has no duration.
"Where, then, is the time that we may call long? Is it future? We do
not say of the future: it _is_ long; for as yet there exists nothing to
be long. We say: it _will be_ long. But when? If while yet future it
will not be long, for nothing will yet exist to be long. And if it will
be long, when, from a future as yet nonexistent, it has become a present,
and has begun to be, that it may be something that is long, then present
time cries out in the words of the preceding paragraph that it cannot be
long."
Augustine's way of presenting the difficulty is a quaint one, but the
problem is as real at the beginning of the twentieth century as it was at
the beginning of the fifth. Past time does not exist now, future time
does not exist yet, and present time, it seems, has no duration. Can a
man be said to be conscious of time as past, present, and future? Who
can be conscious of the nonexistent? And the existent is not _time_, it
has no duration, there is no before and after in a mere limiting point.
Augustine's way out of the difficulty is the suggestion that, although we
cannot, strictly speaking, measure time, we can measure _memory_ and
_expectation_. Before he begins to repeat a psalm, his expectation
extends over the whole of it. After a little a part of it must be
referred to expectation and a part of it to memory. Finally, the whole
psalm is "extended along" the memory. We can measure this, at least.
But how is the psalm in question "extended along" the memory or the
expectation? Are the parts of it successive, or do they thus exist
simultaneously? If everything in the memory image exists at once, if all
belongs to the punctual present, to the mere point that divides past from
future, how can a man get from it a consciousness of time, of a something
whose parts cannot exist together but must follow each other?
Augustine appears to overlook the fact that on his own hypothesis, the
present, the only existent, the only thing a man can be conscious of, is
an indivisible instant. In such there can be no change; the man who is
shut up to such cannot be aware that the past is growing and the future
diminishing. Any such change as this implies at least two instants, an
earlier and a later. He who has never experienced a change of any sort,
who has never been conscious of the relation of earlier and later, of
succession, cannot think of the varied content of memory as of _that
which has been present_. It cannot mean to him what memory certainly
means to us; he cannot be conscious of a past, a present, and a future.
To extract the notion of time, of past, present, and future, from an
experience which contains no element of succession, from an indivisible
instant, is as hopeless a task as to extract a line from a mathematical
point.
It appears, then, that, if we are to be conscious of time at all, if we
are to have the least conception of it, we must have some direct
experience of change. We cannot really be shut up to that punctual
present, that mere point or limit between past and future, that the
present has been described as being. But does this not imply that we can
be directly conscious of what is not present, that we can _now_ perceive
what does _not now_ exist? How is this possible?
It is not easy for one whose reading has been somewhat limited in any
given field to see the full significance of the problems which present
themselves in that field. Those who read much in the history of modern
philosophy will see that this ancient difficulty touching our
consciousness of time has given rise to some exceedingly curious
speculations, and some strange conclusions touching the nature of the
mind.
Thus, it has been argued that, since the experience of each moment is
something quite distinct from the experience of the next, a something
that passes away to give place to its successor, we cannot explain the
consciousness of time, of a whole in which successive moments are
recognized as having their appropriate place, unless we assume a
something that knows each moment and knits it, so to speak, to its
successor. This something is the self or consciousness, which is
independent of time, and does not exist in time, as do the various
experiences that fill the successive moments. It is assumed to be
_timelessly_ present _at all times_, and thus to connect the nonexistent
past with the existent present.
I do not ask the reader to try to make clear to himself how anything can
be timelessly present at all times, for I do not believe that the words
can be made to represent any clear thought whatever. Nor do I ask him to
try to conceive how this timeless something can join past and present. I
merely wish to point out that these modern speculations, which still
influence the minds of many distinguished men, have their origin in a
difficulty which suggested itself early in the history of reflective
thought, and are by no means to be regarded as a gratuitous and useless
exercise of the ingenuity. They are serious attempts to solve a real
problem, though they may be unsuccessful ones, and they are worthy of
attention even from those who incline to a different solution.
29. WHAT IS REAL TIME?--From the thin air of such speculations as we have
been discussing let us come back to the world of the plain man, the world
in which we all habitually live. It is from this that we must start out
upon all our journeys, and it is good to come back to it from time to
time to make sure of our bearings.
We have seen (Chapter V) that we distinguish between the real and the
apparent, and that we recognize as the real world the objects revealed to
the sense of touch. These objects stand to each other in certain
relations of arrangement; that is to say, they exist in space. And just
as we may distinguish between the object as it appears and the object as
it is, so we may distinguish between apparent space and real space,
_i.e._ between the relations of arrangement, actual and possible, which
obtain among the parts of the object as it appears, and those which
obtain among the parts of the object as it really is.
But our experience does not present us only with objects in space
relations; it presents us with a succession of changes in those objects.
And if we will reason about those changes as we have reasoned about space
relations, many of our difficulties regarding the nature of time may, as
it seems, be made to disappear.
Thus we may recognize that we are directly conscious of duration, of
succession, and may yet hold that this crude and immediate experience of
duration is not what we mean by real time. Every one distinguishes
between apparent time and real time now and then. We all know that a
sermon may _seem _long and not _be_ long; that the ten years that we live
over in a dream are not ten real years; that the swallowing of certain
drugs may be followed by the illusion of the lapse of vast spaces of
time, when really very little time has elapsed. What is this _real_ time?
It is nothing else than the order of the changes which take place or may
take place in real things. In the last chapter I spoke of space as the
"form" of the real world; it would be better to call it _a_ "form" of the
real world, and to give the same name also to time.
It is very clear that, when we inquire concerning the real time of any
occurrence, or ask how long a series of such lasted, we always look for
our answer to something that has happened in the external world. The
passage of a star over the meridian, the position of the sun above the
horizon, the arc which the moon has described since our last observation,
the movement of the hands of a clock, the amount of sand which has fallen
in the hourglass, these things and such as these are the indicators of
real time. There may be indicators of a different sort; we may decide
that it is noon because we are hungry, or midnight because we are tired;
we may argue that the preacher must have spoken more than an hour because
he quite wore out the patience of the congregation. These are more or
less uncertain signs of the lapse of time, but they cannot be regarded as
experiences of the passing of time either apparent or real.
Thus, we see that real space and real time are the _plan_ of the world
system. They are not _things_ of any sort, and they should not be
mistaken for things. They are not known independently of things, though,
when we have once had an experience of things and their changes, we can
by abstraction from the things themselves fix our attention upon their
arrangement and upon the order of their changes. We can divide and
subdivide spaces and times without much reference to the things. But we
should never forget that it would never have occurred to us to do this,
indeed, that the whole procedure would be absolutely meaningless to us,
were not a real world revealed in our experience as it is.
He who has attained to this insight into the nature of time is in a
position to offer what seem to be satisfactory solutions to the problems
which have been brought forward above.
(1) He can see, thus, why it is absurd to speak of any portion of time as
becoming nonexistent. Time is nothing else than an order, a great system
of relations. One cannot drop out certain of these and leave the rest
unchanged, for the latter imply the former. Day-after-to-morrow would
not be day-after-to-morrow, if to-morrow did not lie between it and
to-day. To speak of dropping out to-morrow and leaving it the time it
was conceived to be is mere nonsense.
(2) He can see why it does not indicate a measureless conceit for a man
to be willing to say that time is infinite. One who says this need not
be supposed to be acquainted with the whole past and future history of
the real world, of which time is an aspect. We constantly abstract from
things, and consider only the order of their changes, and in this order
itself there is no reason why one should set a limit at some point;
indeed, to set such a limit seems a gratuitous absurdity. He who says
that time is infinite does not say much; he is not affirming the
existence of some sort of a thing; he is merely affirming a theoretical
possibility, and is it not a theoretical possibility that there may be an
endless succession of real changes in a real world?
(3) It is evident, furthermore, that, when one has grasped firmly the
significance of the distinction between apparent time and real time, one
may with a clear conscience speak of time as infinitely divisible. Of
course, the time directly given in any single experience, the minute or
the second of which we are conscious as it passes, cannot be regarded as
composed of an infinite number of parts. We are not directly conscious
of these subdivisions, and it is a monstrous assumption to maintain that
they must be present in the minute or second as perceived.
But no such single experience of duration constitutes what we mean by
real time. We have seen that real time is the time occupied by the
changes in real things, and the question is, How far can one go in the
subdivision of this time?
Now, the touch thing which usually is for us in common life the real
thing is not the real thing for science; it is the appearance under which
the real world of atoms and molecules reveals itself. The atom is not
directly perceivable, and we may assign to its motions a space so small
that no one could possibly perceive it as space, as a something with part
out of part, a something with a here and a there. But, as has been
before pointed out (section 26), this does not prevent us from believing
the atom and the space in which it moves to be real, and we can
_represent_ them to ourselves as we can the things and the spaces with
which we have to do in common life.
It is with time just as it is with space. We can perceive an inch to
have parts; we cannot perceive a thousandth of an inch to have parts, if
we can perceive it at all; but we can represent it to ourselves as
extended, that is, we can let an experience which is extended stand for
it, and can dwell upon the parts of that. We can perceive a second to
have duration; we cannot perceive a thousandth of a second to have
duration; but we can conceive it as having duration, _i.e._ we can let
some experience of duration stand for it and serve as its representative.
It is, then, reasonable to speak of the space covered by the vibration of
an atom, and it is equally reasonable to speak of the time taken up by
its vibration. It is not necessary to believe that the duration that we
actually experience as a second must itself be capable of being divided
up into the number of parts indicated by the denominator of the fraction
that we use in indicating such a time, and that each of these parts must
be perceived as duration.
There is, then, a sense in which we may affirm that time is infinitely
divisible. But we must remember that apparent time--the time presented
in any single experience of duration--is never infinitely divisible; and
that real time, in any save a relative sense of the word, is not a single
experience of duration at all. It is a recognition of the fact that
experiences of duration may be substituted for each other without
assignable limit.
(4) But what shall we say to the last problem--to the question how we can
be conscious of time at all, when the parts of time are all successive?
How can we even have a consciousness of "crude" time, of apparent time,
of duration in any sense of the word, when duration must be made up of
moments no two of which can exist together and no one of which alone can
constitute time? The past is not now, the future is not yet, the present
is a mere point, as we are told, and cannot have parts. If we are
conscious of time as past, present, and future, must we not be conscious
of a series as a series when every member of it save one is nonexistent?
Can a man be conscious of the nonexistent?
The difficulty does seem a serious one, and yet I venture to affirm that,
if we examine it carefully, we shall see that it is a difficulty of our
own devising. The argument quietly makes an assumption--and makes it
gratuitously--with which any consciousness of duration is incompatible,
and then asks us how there can be such a thing as a consciousness of
duration.
The assumption is that _we can be conscious only of the existent_, and
this, written out a little more at length, reads as follows: _we can be
conscious only of the now existent_, or, in other words _of the present_.
Of course, this determines from the outset that we cannot be conscious of
the past and the future, of duration.
The past and the future are, to be sure, nonexistent from the point of
view of the present; but it should be remarked as well that the present
is nonexistent from the point of view of the past or the future. If we
are talking of time at all we are talking of that no two parts of which
are simultaneous; it would be absurd to speak of a past that existed
simultaneously with the present, just as it would be absurd to speak of a
present existing simultaneously with the past. But we should not deny to
past, present, and future, respectively, their appropriate existence; nor
is it by any means self-evident that there cannot be a consciousness of
past, present, and future as such.
We fall in with the assumption, it seems, because we know very well that
we are not directly conscious of a remote past and a remote future. We
represent these to ourselves by means of some proxy--we have present
memories of times long past and present anticipations of what will be in
the time to come. Moreover, we use the word "present" very loosely; we
say the present year, the present day, the present hour, the present
minute, or the present second. When we use the word thus loosely, there
seems no reason for believing that there should be such a thing as a
direct consciousness that extends beyond the present. It appears
reasonable to say: No one can be conscious save of the present.
It should be remembered, however, that the generous present of common
discourse is by no means identical with the ideal point between past and
future dealt with in the argument under discussion. We all say: I now
see that the cloud is moving; I now see that the snow is falling. But
there can be no moving, no falling, no change, in the timeless "now" with
which we have been concerned. Is there any evidence whatever that we are
shut up, for all our immediate knowledge, to such a "now"? There is none
whatever.
The fact is that this timeless "now" is a product of reflective thought
and not a something of which we are directly conscious. It is an ideal
point in the real time of which this chapter has treated, the time that
is in a certain sense infinitely divisible. It is first cousin to the
ideal mathematical point, the mere limit between two lines, a something
not perceptible to any sense. We have a tendency to carry over to it
what we recognize to be true of the very different present of common
discourse, a present which we distinguish from past and future in a
somewhat loose way, but a present in which there certainly is the
consciousness of change, of duration. And when we do this, we dig for
ourselves a pit into which we proceed to fall.
We may, then, conclude that we are directly conscious of more than the
present, in the sense in which Augustine used the word. We are conscious
of _time_, of "crude" time, and from this we can pass to a knowledge of
real time, and can determine its parts with precision.
[1] Book XI, Chapters 14 and 15.
III. PROBLEMS TOUCHING THE MIND
CHAPTER VIII
WHAT IS THE MIND?
30. PRIMITIVE NOTIONS OF MIND.--The soul or mind, that something to
which we refer sensations and ideas of all sorts, is an object that men
do not seem to know very clearly and definitely, though they feel so
sure of its existence that they regard it as the height of folly to
call it in question. That he has a mind, no man doubts; what his mind
is, he may be quite unable to say.
We have seen (section 7) that children, when quite young, can hardly be
said to recognize that they have minds at all. This does not mean that
what is mental is not given in their experience. They know that they
must open their eyes to see things, and must lay their hands upon them
to feel them; they have had pains and pleasures, memories and fancies.
In short, they have within their reach all the materials needed in
framing a conception of the mind, and in drawing clearly the
distinction between their minds and external things. Nevertheless,
they are incapable of using these materials; their attention is
engrossed with what is physical,--with their own bodies and the bodies
of others, with the things that they can eat, with the toys with which
they can play, and the like. It is only later that there emerges even
a tolerably clear conception of a self or mind different from the
physical and contrasted with it.
Primitive man is almost as material in his thinking as is the young
child. Of this we have traces in many of the words which have come to
be applied to the mind. Our word "spirit" is from the Latin
_spiritus_, originally a breeze. The Latin word for the soul, the word
used by the great philosophers all through the Middle Ages, _anima_
(Greek, anemos), has the same significance. In the Greek New
Testament, the word used for spirit (pneuma) carries a similar
suggestion. When we are told in the Book of Genesis that "man became a
living soul," we may read the word literally "a breath."
What more natural than that the man who is just awakening to a
consciousness of that elusive entity the mind should confuse it with
that breath which is the most striking outward and visible sign that
distinguishes a living man from a dead one?
That those who first tried to give some scientific account of the soul
or mind conceived it as a material thing, and that it was sufficiently
common to identify it with the breath, we know from direct evidence. A
glance at the Greek philosophy, to which we owe so much that is of
value in our intellectual life, is sufficient to disclose how difficult
it was for thinking men to attain to a higher conception.
Thus, Anaximenes of Miletus, who lived in the sixth century before
Christ, says that "our soul, which is air, rules us." A little later,
Heraclitus, a man much admired for the depth of his reflections,
maintains that the soul is a fiery vapor, evidently identifying it with
the warm breath of the living creature. In the fifth century, B.C.,
Anaxagoras, who accounts for the ordering of the elements into a system
of things by referring to the activity of Mind or Reason, calls mind
"the finest of things," and it seems clear that he did not conceive of
it as very different in nature from the other elements which enter into
the constitution of the world.
Democritus of Abdera (between 460 and 360 B.C.), that great
investigator of nature and brilliant writer, developed a materialistic
doctrine that admits the existence of nothing save atoms and empty
space. He conceived the soul to consist of fine, smooth, round atoms,
which are also atoms of fire. These atoms are distributed through the
whole body, but function differently in different places--in the brain
they give us thought, in the heart, anger, and in the liver, desire.
Life lasts just so long as we breathe in and breathe out such atoms.
The doctrine of Democritus was taken up by Epicurus, who founded his
school three hundred years before Christ--a school which lived and
prospered for a very long time. Those who are interested in seeing how
a materialistic psychology can be carried out in detail by an ingenious
mind should read the curious account of the mind presented in his great
poem, "On Nature," by the Roman poet Lucretius, an ardent Epicurean,
who wrote in the first century B.C.
The school which we commonly think of contrasting with the Epicurean,
and one which was founded at about the same time, is that of the
Stoics. Certainly the Stoics differed in many things from the
Epicureans; their view of the world, and of the life of man, was a much
nobler one; but they were uncompromising materialists, nevertheless,
and identified the soul with the warm breath that animates man.
31. THE MIND AS IMMATERIAL.--It is scarcely too much to say that the
Greek philosophy as a whole impresses the modern mind as representing
the thought of a people to whom it was not unnatural to think of the
mind as being a breath, a fire, a collection of atoms, a something
material. To be sure, we cannot accuse those twin stars that must ever
remain the glory of literature and science, Plato and Aristotle, of
being materialists. Plato (427-347, B.C.) distributes, it is true, the
three-fold soul, which he allows man, in various parts of the human
body, in a way that at least suggests the Democritean distribution of
mind-atoms. The lowest soul is confined beneath the diaphragm; the one
next in rank has its seat in the chest; and the highest, the rational
soul, is enthroned in the head. However, he has said quite enough
about this last to indicate clearly that he conceived it to be free
from all taint of materiality.
As for Aristotle (384-322, B.C.), who also distinguished between the
lower psychical functions and the higher, we find him sometimes
speaking of soul and body in such a way as to lead men to ask
themselves whether he is really speaking of two things at all; but when
he specifically treats of the _nous_ or reason, he insists upon its
complete detachment from everything material. Man's reason is not
subjected to the fate of the lower psychical functions, which, as the
"form" of the body, perish with the body; it enters from without, and
it endures after the body has passed away. It is interesting to note,
however, an occasional lapse even in Aristotle. When he comes to speak
of the relation to the world of the Divine Mind, the First Cause of
Motion, which he conceives as pure Reason, he represents it as
_touching_ the world, although it remains itself _untouched_. We seem
to find here just a flavor--an inconsistent one--of the material.
Such reflections as those of Plato and Aristotle bore fruit in later
ages. When we come down to Plotinus the Neo-Platonist (204-269, A.D.),
we have left the conception of the soul as a warm breath, or as
composed of fine round atoms, far behind. It has become curiously
abstract and incomprehensible. It is described as an immaterial
substance This substance is, in a sense, in the body, or, at least, it
is present to the body. But it is not in the body as material things
are in this place or in that. _It is as a whole in the whole body, and
it is as a whole in every part of the body_. Thus the soul may be
regarded as divisible, since it is distributed throughout the body; but
it must also be regarded as indivisible, since it is wholly in every
part.
Let the man to whom such sentences as these mean anything rejoice in
the meaning that he is able to read into them! If he can go as far as
Plotinus, perhaps he can go as far as Cassiodorus (477-570, A.D.), and
maintain that the soul is not merely as a whole in every part of the
body, but is wholly in each of its own parts.
Upon reading such statements one's first impulse is to exclaim: How is
it possible that men of sense should be led to speak in this
irresponsible way? and when they do speak thus, is it conceivable that
other men should seriously occupy themselves with what they say?
But if one has the historic sense, and knows something of the setting
in which such doctrines come to the birth, one cannot regard it as
remarkable that men of sense should urge them. No one coins them
independently out of his own brain; little by little men are impelled
along the path that leads to such conclusions. Plotinus was a careful
student of the philosophers that preceded him. He saw that mind must
be distinguished from matter, and he saw that what is given a location
in space, in the usual sense of the words, is treated like a material
thing. On the other hand, he had the common experience that we all
have of a relation between mind and body. How do justice to this
relation, and yet not materialize mind?
What he tried to do is clear, and it seems equally clear that he had
good reason for trying to do it. But it appears to us now that what he
actually did was to make of the mind or soul a something very like an
inconsistent bit of matter, that is somehow in space, and yet not
exactly in space, a something that can be in two places at once, a
logical monstrosity. That his doctrine did not meet with instant
rejection was due to the fact, already alluded to, that our experience
of the mind is something rather dim and elusive. It is not easy for a
man to say what it is, and, hence, it is not easy for a man to say what
it is not.
The doctrine of Plotinus passed over to Saint Augustine, and from him
it passed to the philosophers of the Middle Ages. How extremely
difficult it has been for the world to get away from it at all, is made
clearly evident in the writings of that remarkable man Descartes.
Descartes wrote in the seventeenth century. The long sleep of the
Middle Ages was past, and the several sciences had sprung into a
vigorous and independent life. It was not enough for Descartes to
describe the relation of mind and body in the loose terms that had
prevailed up to his time. He had made a careful study of anatomy, and
he realized that the brain is a central organ to which messages are
carried by the nerves from all parts of the body. He knew that an
injury to the nerve might prevent the receipt of a message, _i.e._ he
knew that a conscious sensation did not come into being until something
happened in the brain.
Nor was he content merely to refer the mind to the brain in a general
way. He found the "little pineal gland" in the midst of the brain to
be in what he regarded as an admirable position to serve as the seat of
the soul. To this convenient little central office he relegated it;
and he describes in a way that may to-day well provoke a smile the
movements that the soul imparts to the pineal gland, making it incline
itself in this direction and in that, and making it push the "animal
spirits," the fluid contained in the cavities of the brain, towards
various "pores."
Thus he writes:[1] "Let us, then, conceive of the soul as having her
chief seat in the little gland that is in the middle of the brain,
whence she radiates to all the rest of the body by means of the
spirits, the nerves, and even the blood, which, participating in the
impressions of the spirits, can carry them through the arteries to all
the members." And again: "Thus, when the soul wills to call anything
to remembrance, this volition brings it about that the gland, inclining
itself successively in different directions, pushes the spirits towards
divers parts of the brain, until they find the part which has the
traces that the object which one wishes to recollect has left there."
We must admit that Descartes' scientific studies led him to make this
mind that sits in the little pineal gland something very material. It
is spoken of as though it pushed the gland about; it is affected by the
motions of the gland, as though it were a bit of matter. It seems to
be a less inconsistent thing than the "all in the whole body" soul of
Plotinus; but it appears to have purchased its comprehensibility at the
expense of its immateriality.
Shall we say that Descartes frankly repudiated the doctrine that had
obtained for so many centuries? We cannot say that; he still held to
it. But how could he? The reader has perhaps remarked above that he
speaks of the soul as having her _chief_ seat in the pineal gland. It
seems odd that he should do so, but he still held, even after he had
come to his definite conclusions as to the soul's seat, to the ancient
doctrine that the soul is united to all the parts of the body
"conjointly." He could not wholly repudiate a venerable tradition.
We have seen, thus, that men first conceived of the mind as material
and later came to rebel against such a conception. But we have seen,
also, that the attempt to conceive it as immaterial was not wholly
successful. It resulted in a something that we may describe as
inconsistently material rather than as not material at all.
32. MODERN COMMON SENSE NOTIONS OF THE MIND.--Under this heading I mean
to sum up the opinions as to the nature of the mind usually held by the
intelligent persons about us to-day who make no claim to be regarded as
philosophers. Is it not true that a great many of them believe:--
(1) That the mind is in the body?
(2) That it acts and reacts with matter?
(3) That it is a substance with attributes?
(4) That it is nonextended and immaterial?
I must remark at the outset that this collection of opinions is by no
means something gathered by the plain man from his own experience.
These opinions are the echoes of old philosophies. They are a heritage
from the past, and have become the common property of all intelligent
persons who are even moderately well-educated. Their sources have been
indicated in the preceding sections; but most persons who cherish them
have no idea of their origin.
Men are apt to suppose that these opinions seem reasonable to them
merely for the reason that they find in their own experience evidence
of their truth. But this is not so.
Have we not seen above how long it took men to discover that they must
not think of the mind as being a breath, or a flame, or a collection of
material atoms? The men who erred in this way were abler than most of
us can pretend to be, and they gave much thought to the matter. And
when at last it came to be realized that mind must not thus be
conceived as material, those who endeavored to conceive it as something
else gave, after their best efforts, a very queer account of it indeed.
Is it in the face of such facts reasonable to suppose that our friends
and acquaintances, who strike us as having reflective powers in nowise
remarkable, have independently arrived at the conception that the mind
is a nonextended and immaterial substance? Surely they have not
thought all this out for themselves. They have taken up and
appropriated unconsciously notions which were in the air, so to speak.
They have inherited their doctrines, not created them. It is well to
remember this, for it may make us the more willing to take up and
examine impartially what we have uncritically turned into articles of
belief.
The first two articles, namely, that the mind is in the body and that
it acts upon, and is acted upon by, material things, I shall discuss at
length in the next chapter. Here I pause only to point out that the
plain man does not put the mind into the body quite unequivocally. I
think it would surprise him to be told that a line might be drawn
through two heads in such a way as to transfix two minds. And I
remark, further, that he has no clear idea of what it means for mind to
act upon body or body to act upon mind. How does an immaterial thing
set a material thing in motion? Can it touch it? Can it push it?
Then what does it do?
But let us pass on to the last two articles of faith mentioned above.
We all draw the distinction between _substance_ and its _attributes_ or
_qualities_. The distinction was remarked and discussed many centuries
ago, and much has been written upon it. I take up the ruler on my
desk; it is recognized at once as a bit of wood. How? It has such and
such qualities. My paper-knife is of silver. How do I know it? It
has certain other qualities. I speak of my mind. How do I know that I
have a mind? I have sensations and ideas. If I experienced no mental
phenomena of any sort, evidence of the existence of a mind would be
lacking.
Now, whether I am concerned with the ruler, with the paper-knife, or
with the mind, have I direct evidence of the existence of anything more
than the whole group of qualities? Do I ever perceive the substance?
In the older philosophy, the substance (_substantia_) was conceived to
be a something not directly perceived, but only inferred to exist--a
something underlying the qualities of things and, as it were, holding
them together. It was believed in by philosophers who were quite ready
to admit that they could not tell anything about it. For example, John
Locke (1632-1704), the English philosopher, holds to it stoutly, and
yet describes it as a mere "we know not what," whose function it is to
hold together the bundles of qualities that constitute the things we
know.
In the modern philosophy men still distinguish between substance and
qualities. It is a useful distinction, and we could scarcely get on
without it. But an increasing number of thoughtful persons repudiate
the old notion of substance altogether.
We may, they say, understand by the word "substance" the whole group of
qualities _as a group_--not merely the qualities that are revealed at a
given time, but all those that we have reason to believe a fuller
knowledge would reveal. In short, we may understand by it just what is
left when the "we know not what" of the Lockian has been discarded.
This notion of substance we may call the more modern one; yet we can
hardly say that it is the notion of the plain man. He does not make
very clear to himself just what is in his thought, but I think we do
him no injustice in maintaining that he is something of a Lockian, even
if he has never heard of Locke. The Lockian substance is, as the
reader has seen, a sort of "unknowable."
And now for the doctrine that the mind is nonextended and immaterial.
With these affirmations we may heartily agree; but we must admit that
the plain man enunciates them without having a very definite idea of
what the mind is.
He regards as in his mind all his sensations and ideas, all his
perceptions and mental images of things. Now, suppose I close my eyes
and picture to myself a barber's pole. Where is the image? We say, in
the mind. Is it extended? We feel impelled to answer, No. But it
certainly _seems_ to be extended; the white and the red upon it appear
undeniably side by side. May I assert that this mental image has no
extension whatever? Must I deny to it _parts_, or assert that its
parts are not side by side?
It seems odd to maintain that a something as devoid of parts as is a
mathematical point should yet appear to have parts and to be extended.
On the other hand, if we allow the image to be extended, how can we
refer it to a nonextended mind?
To such questions as these, I do not think that the plain man has an
answer. That they can be answered, I shall try to show in the last
section of this chapter. But one cannot answer them until one has
attained to rather a clear conception of what is meant by the mind.
And until one has attained to such a conception, the statement that the
mind is immaterial must remain rather vague and indefinite. As we saw
above, even the Plotinic soul was inconsistently material rather than
immaterial. It was not excluded from space; it was referred to space
in an absurd way. The mind as common sense conceives it, is the
successor of this Plotinic soul, and seems to keep a flavor of what is
material after all. This will come out in the next chapter, where we
shall discuss mind and body.
33. THE PSYCHOLOGIST AND THE MIND.--When we ask how the psychologist
conceives of the mind, we must not forget that psychologists are many
and that they differ more or less from each other in their opinions.
When we say "the psychologist" believes this or that, we mean usually
no more than that the opinion referred to is prevalent among men of
that class, or that it is the opinion of those whom we regard as its
more enlightened members.
Taking the words in this somewhat loose sense, I shall ask what the
psychologist's opinion is touching the four points set forth in the
preceding section. How far does he agree with the plain man?
(1) There can be no doubt that he refers the mind to the body in some
way, although he may shake his head over the use of the word "in."
(2) As to whether the mind acts and reacts with matter, in any sense of
the words analogous to that in which they are commonly used, there is a
division in the camp. Some affirm such interaction; some deny it. The
matter will be discussed in the next chapter.
(3) The psychologist--the more modern one--inclines to repudiate any
substance or substratum of the sort accepted in the Middle Ages and
believed in by many men now. To him the mind is the whole complex of
mental phenomena in their interrelations. In other words, the mind is
not an unknown and indescribable something that is merely inferred; it
is something revealed in consciousness and open to observation. |
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