> attack made by Plato on himself in the "Phaedo" through Simmias and Kebes.

It is only apparently that the modern attacks have become more serious

through the deepened knowledge of natural science. At all times they have

been as serious and as significant as possible, and the religious and

every other idealistic conception of the universe has always suffered from

them. It is plain that here, if anywhere, "faith goes against

appearances," and that in the last resource we have to postulate free

moral resolution, the will to believe, the desire for the ideal, for

freedom, and for the eternity of the spirit, and the confidence of the

spirit in itself. All this is, or at least ought to be, self-evident and

generally admitted.



Let us once more take a brief survey of the reasons on the other side and

arrange them in order.



That nature is everything and spirit very little seems to follow from a

very simple circumstance. There are whole worlds of purely natural and

corporeal existence without mind, sensation, or consciousness, which,

quite untroubled by their absence, simply exist according to the

everlasting laws of matter and energy. But nowhere do we find spirit or

mind without a material basis. All that is psychical occurs in connection

with a physical being, and with relatively few physical beings. Spirit

seems wholly bound up with and dependent upon the states, development, and

conditions of material being. With the body of living beings there arises

what we call "soul"; with the body it grows, gains content, changes,

matures, ages, and disappears. According as the body is constituted and

composed, as it is influenced by heredity, race, and selection, by

nutrition, mode of life, climate, and other circumstances, there are

developed in a hundred different ways what we call the natural disposition

or character, inclinations, virtues or vices, passions or temperaments.

Even the names given to the different temperaments emphasise this

dependence of what is innermost in us, the deepest tendencies of our

being, on the bodily organisation and the nature of its physiological

constitution. The man whose blood flows easily and freely is called

sanguine, and the melancholic is the victim of his liver. According as our

organs are good or bad, function freely or sluggishly, our mood rises or

sinks, we are bold or cowardly, languid or impetuous, and enthusiasm is

often enough only a peculiar name for a state which, physiologically

expressed, might be called alcoholic poisoning. There is one soul in the

sound body, another in the sickly. Fever, and the impotence of the soul

against it, made Holbach a materialist. If the brain be diseased, that

marvellous order of psychical processes which we call reasoning is broken;

the "soul" is wholly or partly eliminated; it fades away, or becomes

nothing more than a confused disconnected medley of images and desires.

Even artificial interference with, and changes in the bodily organisation

react upon the mind. The removal of the thyroid gland may result in

idiocy. Castration not only prevents the "breaking" of the voice in the

Sistine choristers, it damps the fires of life to dulness, and makes of

the impetuous Abelard a comfortable discursive father-confessor. The mind

is bound up almost piece by piece with its material basis. Through the

"localisation" of psychic processes in the particular parts of the brain,

naturalism has enormously strengthened the impression that existed even

among the ancients, that sensation and imagination are nothing more than,

let us say, what the note is to a tightly stretched string. Cerebrum and

cerebellum are regarded as the seats of different psychic processes. The

secret of the higher processes is believed to be hidden in the grey matter

of the cortex of the cerebrum. We seek and find in the various lobes and

convolutions of the brain the "centres" for the different capacities, the

power of sight, of smell, of moving the arms, of moving the legs, of

associating ideas, of co-ordinated speech, and so on. When brain and

spinal cord are injured or removed piece by piece from a pigeon or a frog,

it seems as if the "soul" were eliminated piece by piece,--the capacity for

spontaneous free co-ordination, for voluntary action, for the various

sense-impressions, and so on from the higher to the lower. It has even

been maintained that the different feelings and perceptions which are

gradually acquired can be apportioned among the individual cells of the

brain in which they are localised, and the thought-processes, the

associations of percepts, the origin of consecutive ideas, the rapid and

easy recalling of memory-images, and the process of voluntary control, of

instincts, can be explained as due to the "gradual laying down of

nerve-paths" between the different centres and areas of localisation in

the brain. All this seems to refute utterly the old belief in the unity

and personality of the soul. It is different in youth and in age, and

indeed varies continually. It is the ever-varied harmony of the notes of

all the strings which are represented by the fibres and ganglion-cells of

the nerve-substance. It apparently can not only be completely confused and

brought to disharmony, but it may be halved and divided. An almost

terrifying impression was produced when Trembley in 1740 made the

experiment of cutting a "hydra" in two, and showed that each of the halves

became a complete animal, so that obviously each of the two halves of the

soul grew into a new hydra-soul. And Trembley's hydra was only the

precursor of all the cut-up worms, of the frogs, birds, and guinea-pigs

that have been beheaded, or have had their brain removed, or their nerves

cut, and have furnished further examples of this divisibility of "souls."



If the independence of the spiritual is thus shown to be a vain

assumption, the alleged difference between the animal and the human Psyche

is much more so. Not from the days of Darwinism alone, but from the very

beginning, naturalism has opposed this claim to distinctiveness. But it is

due to Darwinism that the fundamental similarity of the psychical in man

and animals has come to be regarded as almost self-evident. The mental

organisation of man, as well as his corporeal organisation, is traced back

through gradual stages to animal antecedents, and in thus tracing it there

are two favourite methods of procedure, which are, however, apt to be

mutually destructive.



On the one hand, some naturalists regard the animal anthropomorphically,

insist on its likeness to man, discovering and extolling, not without

emotion, all the higher and nobler possessions of the human mind,

intellectual capacities, reason, reflection, synthesis, fancy, the power

of forming ideas and judgments, of drawing conclusions and learning from

experience, besides will in the true sense, ethical, social and political

capacities, aesthetic perceptions, and even fits of religion in elephants,

apes, dogs, down even to ants and bees, and these naturalists reject

old-fashioned explanations in terms of instinct, and find the highest

already contained in the lowest. Those of another school are inclined to

regard man theriomorphically, to insist on his likeness to animals,

explaining reason in terms of perception and sensation, deriving will from

impulse and desire, and ethical and aesthetic valuations from physiological

antecedents and purely animal psychological processes, thus, in short,

seeking to find the lowest in the highest. (We have already met with an

analogous instance of a similarly fallacious double-play on parallel

lines.) So it comes about that both the origin and the development of the

psychical and spiritual seem to be satisfactorily cleared up and

explained, and at the same time a new proof is adduced for its dependence

upon the physical. For what is true of all other parts of the

organisation, of the building up and perfecting of every member and every

system of organs, the bony skeleton, the circulatory system, the

alimentary canal, that they can be referred back to very simple



beginnings, and that their evolution may be traced through all its

stages--is equally true of the nervous system in general and of the brain

in particular. It increases more and more in volume and in intricacy of

structure, it expands the cranial cavity and diversifies its convolutions.

And the more it grows, and the more complex it becomes, the more do the

mental capacities increase in perfection, so that here again it seems once

more apparent that the psychical is an accompaniment and result of the

physical.



Popular naturalism usually stops short here, and contents itself with

half-truths and inconsequences, for it naively admits that psychical

processes, sensation, perception, will, have a real influence upon the

physical, and, not perceiving how much the admission involves, it does not

trouble itself over the fact that, for instance in the so-called voluntary

movements of the body, in ordinary behaviour, the psychical, and the will,

in particular, is capable of real effect, and can move hand and foot and

the whole body, and thus has a real reciprocal relation with the physical.

This form of popular naturalism sometimes amuses itself with assuming a

psychical inwardness even in non-living matter, and admitting the

co-operation of psychical motives even in regard to it.



But it is far otherwise with naturalism in the strict sense, which takes

its fundamental principles and its method of investigation seriously. It

is aware that such half-and-half measures interrupt the continuity of the

system at the most decisive point. And therefore with the greatest

determination it repeats along psychological lines the same kind of

treatment that it has previously sought to apply to biological phenomena:

the corporeal must form a sequence of phenomena complete in itself and not

broken into from without. All processes of movement, all that looks as if

it happened "through our will," through a resolve due to the intervention

of a psychical motive, every flush of shame that reddens the cheek, every

stroke executed by the hand, every sound-wave caused by tongue and lips,

must be the result of conditions of stimulation and tension in the energy

of the body itself.



This is the meaning of all those psycho-physical experiments that have

been carried on with so much ingenuity and persistence (usually associated

with attempts to explain vital phenomena in terms of mechanism). First,

they attempt to interpret the expressions of will, feeling and need, the

spontaneous activities and movements of the lowest forms of

life--protists--as "pure reflexes," as processes which take place in

obedience to stimuli, and thus are ultimately due to chemical and physical

influences and causes without the intervention of a psychical motive; and,

secondly, when this has been apparently or really achieved, the theory of

irritability and reflex mechanism is pushed from below upwards, until even

the most intricate and complex movements and operations of our own body,

which we have wrongly distinguished as acts or behaviour from mere

processes of stimulation, are finally recognised as reflexes and

liberations due to stimuli. Some stimulus or other, from light or sound or

something else, is, according to this theory, conducted to the nervous

centre, the ganglion, the spinal cord, the cerebellum or the cerebrum.

Here it produces an effect, not of a psychical nature, but some minute

chemical, or physical,--or purely mechanical change, which goes through

many permutations within the nervous centre itself, unites there with the

stored energies, and then, thus altered, returns by the efferent nerve

paths to effect a muscle-contraction in some organ, a stretching of the

hand, or a movement of the whole body. The physical process is accompanied

by a peculiar inward mirroring, which is the psychical penumbra or shadow

of the whole business. Thus what is in reality a purely mechanical and

reflex sequence appears like a psychical experience, like choice and will

and psychical causality. We may be compared to Spinoza's stone; it was

thrown, and it thought it was flying.



The reasons for interpreting things in this way lie in the principles of

investigation. It is only in this way, we are told, that nature can be

reduced to natural terms, that is, to chemistry, physics, and mechanics.

Only in this way is it possible to gain a true insight into and

understanding of things, and to bring them under mathematical formulae.

Thus only, too, can "the miraculous" be eliminated. For if we are obliged

to admit that the will has a real influence on the corporeal, for instance

upon our brain, and nerves, and arm-muscles, this would be a violation of

the law of the constancy of the sum of energy. For in this case there

would occur, at a certain point in the nexus of phenomena, a piece of work

done, however small it might be, for which there was no equivalent of

energy in the previous constitution. But this is, since the days of

Helmholtz, an impossible assumption. And thus all those experiments and

theories on what we have called the "second line" of mechanistic

interpretation of the universe show themselves to be relevant to our

present subject.



Interpretations of the psychical such as these have given rise to four

peculiar "isms" of an epistemological nature, i.e., related to a theory

of knowledge. Not infrequently they are the historical antecedents which

result in the naturalistic theory of the psychical. These are nominalism

and sensualism, empiricism and a-posteriorism, which, setting themselves

against epistemological rationalism, assail the dignity, the independence,

and the autonomy of the thinking mind. They are so necessarily and closely

associated with naturalism that their fate is intimately bound up with its

fate, and they are corroborated or refuted with it. And it would be

possible to conduct the whole discussion with which we are concerned

purely with reference to these four "isms." The strife really begins in

their camp.



The soul is a tabula rasa, all four maintain, a white paper on which, to

begin with, nothing is inscribed. It brings with it neither innate

knowledge nor commands. What it possesses in the way of percepts,

concepts, opinions, convictions, principles of action, rules of conduct,

are inscribed upon it through experience (empiricism). That is, not

antecedent to, but subsequent to experience (a posteriori). But experience

can only be gained through the senses. Only thus does reality penetrate

into and stamp itself upon us. "What was not first in the senses (sensus)

cannot be in the intelligence." What the senses convey to us alone builds

up our mental content, from mere sensory perceptions upwards to the most

abstract ideas from the simplest psychical elements up to the most complex

ideas, concepts, and conclusions, to the most varied imaginative

constructions. And in the development of the mental content the "soul"

itself is merely the stage upon which all that is acquired through the

senses crowds, and jostles, and unites to form images, perceptions, and

precepts. But it is itself purely passive, and it becomes what happens to

it. Therefore it is not really spirit at all, for spirit implies

spontaneity, activity, and autonomy.



Philosophy and the mental sciences have always had to carry on the strife

with these four opponents. And it is in the teacup of logic and

epistemology that the storm in regard to theories of the universe has

arisen. It is there, and not in the domain of neurology, or zoology, that

the real battlefield lies, upon which the controversy must be fought out

to the end. What follows is only a sort of skirmish about the outposts.



What naturalism holds in regard to the psychical and spiritual may be,

perhaps, most simply expressed by means of an illustration. Over a wide

field there glide mighty shadows in constant interplay. They expand and

contract, become denser or lighter, disappear for a little, and then

reveal themselves again. While they are thus forming and changing, one

state follows quite connectedly on another. At first one is tempted to

believe that they are self-acting and self-regulating, that they move

freely and pass from one state to another according to causes within

themselves. But then one sees that they are thrown upon the earth from the

clouds above, now in this way and now in that, that all their states and

forms and changes are nothing in themselves, and neither effect anything

in themselves nor react upon the occurrences and realities up above, which

they only accompany, and by which they are determined without any

co-operation on their own part, even in determining their own form. So it

is with nature and spirit. Nature is the true effective reality; spirit is

its shadow, which effects nothing either within or outside of itself, but

simply happens.