An Introduction to Philosophy Part 21

With a view to showing the truth of this opinion, I shall take up one by one the philosophical sciences. Of the history of philosophy I shall not speak in this part of the work, but shall treat of it in Chapter XXIII.

66. THE TRADITIONAL LOGIC.--Most of us begin our acquaintance with logic in the study of some such elementary manual as Jevons' "Lessons in Logic."

In such books we are shown how terms represent things and cla.s.ses of things or their attributes, and how we unite them into propositions or statements. It is indicated at length what statements may be made on a basis of certain other statements and what may not; and emphasis is laid upon the dangers which arise out of a misunderstanding of the language in which we are forced to express our thoughts. Finally, there are described for us the experimental methods by which the workers in the sciences have attained to the general information about the world which has become our heritage.

Such books are useful. It is surely no small profit for a student to gain the habit of scrutinizing the steps by which he has come into the possession of a certain bit of information, and to have a quick eye for loose and inconsistent reasonings.

But it is worthy of remark that one may study such a book as this and yet remain pretty consistently on what may be called the plane of the common understanding. One seems to make the a.s.sumptions made in all the special sciences, _e.g._ the a.s.sumption that there is a world of real things and that we can know them and reason about them. We are not introduced to such problems as: What _is_ truth? and Is _any_ knowledge valid? Nor does it seem at once apparent that the man who is studying logic in this way is busying himself with a philosophical discipline.

67. THE "MODERN LOGIC."--It is very puzzling for the student to turn from such a text-book as the one above mentioned to certain others which profess to be occupied with the same science, and which, yet, appear to treat of quite different things.

Thus, in Dr. Bosanquet's little work on "The Essentials of Logic," the reader is at once plunged into such questions as the nature of knowledge, and what is meant by the real world. We seem to be dealing with metaphysics, and not with logic, as we have learned to understand the term. How is it that the logician comes to regard these things as within his province?

A mult.i.tude of writers at the present day are treating logic in this way, and in some great prominence is given to problems which the philosopher recognizes as indisputably his own. The term "modern logic" is often employed to denote a logic of this type; one which does not, after the fas.h.i.+on of the natural sciences generally, proceed on the basis of certain a.s.sumptions, and leave deeper questions to some other discipline, but tries to get to the bottom of things for itself.

The tendency to run into metaphysics is peculiarly marked in those writers who have been influenced by the work of the philosopher Hegel.

I shall not here ask why those who belong to one school are more inclined to be metaphysical than are those who belong to another, but shall approach the broader question why the logicians generally are inclined to be more metaphysical than those who work in certain other special sciences, such as mathematics, for example. Of the general tendency there can be no question. The only problem is: Why does this tendency exist?

68. LOGIC AND PHILOSOPHY.--Let us contrast the science of arithmetic with logic; and let us notice, regarding it, the following points:--

It is, like logic, a _general_ science, in that the things treated of in many sciences may be numbered. It considers only a certain aspect of the things.

Now, that things may be counted, added together, subtracted, etc., is guaranteed by the experience of the plain man; and the methods of determining the numerical relations of things are gradually developed before his eyes, beginning with operations of great simplicity.

Moreover, verification is possible, and within certain limits verification by direct inspection.

To this we may add, that there has gradually been built up a fine system of unambiguous symbols, and it is possible for a man to know just what he is dealing with.

Thus, a certain beaten path has been attained, and a man may travel this very well without having forced on his attention the problems of reflective thought. The knowledge of numbers with which he starts is sufficient equipment with which to undertake the journey. That one is on the right road is proved by the results one obtains. As a rule, disputes can be settled by well-tried mathematical methods.

There is, then, a common agreement as to initial a.s.sumptions and methods of work, and useful results are attained which seem to justify both. Here we have the normal characteristics of a special science.

We must not forget, however, that, even in the mathematical sciences, before a beaten path was attained, disputes as to the significance of numbers and the cogency of proofs were sufficiently common. And we must bear in mind that even to-day, where the beaten path does not seem wholly satisfactory, men seem to be driven to reflect upon the significance of their a.s.sumptions and the nature of their method.

Thus, we find it not unnatural that a man should be led to ask; What is a minus quant.i.ty really? Can anything be less than nothing? or that he should raise the questions: Can one rightly speak of an infinite number? Can one infinite number be greater than another, and, if so, what can greater mean? What are infinitesimals? and what can be meant by different orders of infinitesimals?

He who has interested himself in such questions as these has betaken himself to philosophical reflection. They are not answered by employing mathematical methods.

Let us now turn to logic. And let us notice, to begin with, that it is broader in its application than the mathematical sciences. It is concerned to discover what const.i.tutes _evidence_ in every field of investigation.

There is, it is true, a part of logic that may be developed somewhat after the fas.h.i.+on of mathematics. Thus, we may examine the two statements: All men are mortal, and Caesar is a man; and we may see clearly that, given the truth of these, we must admit that Caesar is mortal. We may make a list of possible inferences of this kind, and point out under what circ.u.mstances the truth of two statements implies the truth of a third, and under what circ.u.mstances the inference cannot be made. Our results can be set forth in a system of symbols. As in mathematics, we may abstract from the particular things reasoned about, and concern ourselves only with the forms of reasoning. This gives us the theory of the _syllogism_; it is a part of logic in which the mathematician is apt to feel very much at home.

But this is by no means all of logic. Let us consider the following points:--

(1) We are not concerned to know only what statements may be made on the basis of certain other statements. We want to know what is true and what is false. We must ask: Has a man the right to set up these particular statements and to reason from them? That some men accept as true premises which are repudiated by others is an undoubted fact.

Thus, it is maintained by certain philosophers that we may a.s.sume that any view of the universe which is repellant to our nature cannot be true. Shall we allow this to pa.s.s unchallenged? And in ethics, some have held that it is under all circ.u.mstances wrong to lie; others have denied this, and have held that in certain cases--for example, to save life or to prevent great and unmerited suffering--lying is permissible.

Shall we interest ourselves only in the deductions that each man makes from his a.s.sumed premises, and pay no attention to the truth of the premises themselves?

(2) Again. The vast ma.s.s of the reasonings that interest men are expressed in the language that we all use and not in special symbols.

But language is a very imperfect instrument, and all sorts of misunderstandings are possible to those who express their thoughts in it.

Few men know exactly how much is implied in what they are saying. If I say: All men are mortal, and an angel is not a man; therefore, an angel is not mortal; it is not at once apparent to every one in what respect my argument is defective. He who argues: Feathers are light; light is contrary to darkness; hence, feathers are contrary to darkness; is convicted of error without difficulty. But arguments of the same kind, and quite as bad, are to be found in learned works on matters less familiar to us, and we often fail to detect the fallacy.

Thus, Herbert Spencer argues, in effect, in the fourth and fifth chapters of his "First Principles," as follows:--

We are conscious of the Unknowable, The Unknowable lies behind the veil of phenomena, Hence, we are conscious of what lies behind the veil of phenomena.

It is only the critical reader who notices that the Unknowable in the first line is the "raw material of consciousness," and the Unknowable in the second is something not in consciousness at all. The two senses of the word "light" are not more different from one another. Such apparent arguments abound, and it often requires much acuteness to be able to detect their fallacious character.

When we take into consideration the two points indicated above, we see that the logician is at every turn forced to reflect upon our knowledge as men do not ordinarily reflect. He is led to ask: What is truth? He cannot accept uncritically the a.s.sumptions which men make; and he must endeavor to become very clearly conscious of the real meaning and the whole meaning of statements expressed in words. Even in the simple logic with which we usually begin our studies, we learn to scrutinize statements in a reflective way; and when we go deeper, we are at once in contact with philosophical problems. It is evidently our task to attain to a clearer insight into the nature of our experience and the meaning of proof than is attainable by the unreflective.

Logic, then, is a reflective science, and it is not surprising that it has held its place as one of the philosophical sciences.

CHAPTER XVII

PSYCHOLOGY

69. PSYCHOLOGY AND PHILOSOPHY.--I think I have said enough in Chapter II (section 10) about what we mean when we speak of psychology as a natural science and as an independent discipline. Certainly there are many psychologists who would not care to be confused with the philosophers, and there are some that regard philosophy with suspicion.

Nevertheless, psychology is commonly regarded as belonging to the philosophical group. That this is the case can scarcely be thought surprising when we see how the psychologist himself speaks of the relation of his science to philosophy.

"I have kept," writes Professor James[1] in that delightful book which has become the common property of us all, "close to the point of view of natural science throughout the book. Every natural science a.s.sumes certain data uncritically, and declines to challenge the elements between which its own 'laws' obtain, and from which its own deductions are carried on. Psychology, the science of finite individual minds, a.s.sumes as its data (1) _thoughts and feelings_, and (2) _a physical world_ in time and s.p.a.ce with which they coexist, and which (3) _they know_. Of course, these data themselves are discussable; but the discussion of them (as of other elements) is called metaphysics and falls outside the province of this book."

This is an admirable statement of the scope of psychology as a natural science, and also of the relations of metaphysics to the sciences. But it would not be fair to Professor James to take this sentence alone, and to a.s.sume that, in his opinion, it is easy to separate psychology altogether from philosophy. "The reader," he tells us in the next paragraph, "will in vain seek for any closed system in the book. It is mainly a ma.s.s of descriptive details, running out into queries which only a metaphysics alive to the weight of her task can hope successfully to deal with." And in the opening sentence of the preface he informs us that some of his chapters are more "metaphysical" than is suitable for students going over the subject for the first time.

That the author is right in maintaining that it is not easy to draw a clear line between philosophy and psychology, and to declare the latter wholly independent, I think we must concede. An independent science should be sure of the things with which it is dealing. Where these are vague and indefinite, and are the subject of constant dispute, it cannot march forward with a.s.surance. One is rather forced to go back and examine the data themselves. The beaten track of the special science has not been satisfactorily constructed.

We are forced to admit that the science of psychology has not yet emerged from the state in which a critical examination of its foundations is necessary, and that the construction of the beaten path is still in progress. This I shall try to make clear by ill.u.s.trations.

The psychologist studies the mind, and his ultimate appeal must be to introspection, to a direct observation of mental phenomena, and of their relations to external things. Now, if the observation of mental phenomena were a simple and an easy thing; if the mere fact that we are conscious of sensations and ideas implied that we are _clearly_ conscious of them and are in a position to describe them with accuracy, psychology would be a much more satisfactory science than it is.

But we are not thus conscious of our mental life. We can and do use our mental states without being able to describe them accurately. In a sense, we are conscious of what is there, but our consciousness is rather dim and vague, and in our attempts to give an account of it we are in no little danger of giving a false account.

Thus, the psychologist a.s.sumes that we perceive both physical phenomena and mental--the external world and the mind. He takes it for granted that we perceive mental phenomena to be related to physical. He is hardly in a position to make this a.s.sumption, and then to set it aside as a thing he need not further consider. Does he not tell us, as a result of his investigations, that we can know the external world only as it is reflected in our sensations, and thus seem to shut the mind up within the circle of mental phenomena merely, cutting off absolutely a direct knowledge of what is extra-mental? If we can know only mental phenomena, the representatives of things, at first hand, how can we tell that they are representatives? and what becomes of the a.s.sumption that we _perceive_ that mind is related to an external world?

It may be said, this problem the psychologist may leave to the metaphysician. Certainly, it is one of those problems that the metaphysician discusses; it has been treated in Chapter IV. But my contention is, that he who has given no thought to the matter may easily fall into error as to the very nature of mental phenomena.

For example, when we approach or recede from a physical object we have a series of experiences which are recognized as sensational. When we imagine a tree or a house we are also experiencing a mental phenomenon.

All these experiences _seem_ plainly to have extension in some sense of the word. We appear to perceive plainly part out of part. In so far, these mental things seem to resemble the physical things which we contrast with what is mental. Shall we say that, because these things are mental and not physical, their apparent extension is a delusion?

Shall we say that they really have no parts? Such considerations have impelled psychologists of eminence to maintain, in flat contradiction to what seems to be the unequivocal testimony of direct introspection, that the total content of consciousness at any moment must be looked upon as an indivisible, part-less unit.

We cannot, then, depend merely on direct introspection. It is too uncertain in its deliverances. If we would make clear to ourselves what mental phenomena really are, and how they | differ from physical phenomena, we must fall back upon the reflective a.n.a.lysis of our experience which occupies the metaphysician (section 34). Until we have done this, we are in great danger of error. We are actually uncertain of our materials.

Again. The psychologist speaks of the relation of mind and body. Some psychologists incline to be parallelists, some are warm advocates of interactionism. Now, any theory of the relation of mind to body must depend on observation ultimately. If we had not direct experience of a relation between the physical and the mental somewhere, no hypothesis on the subject would ever have emerged.

But our experiences are not perfectly clear and unequivocal to us.