MENTAL SCIENCE.

Otago Daily Times, Issue 7557, 7 May 1886, Page 4

MENTAL SCIENCE.

PROFESSOR SALMOND'S INTRODUC-

TORY LECTURE.

The following is a resume of Professor Salmond's introductory lecture delivered to his class on Monday evening last. About 15 students were present, and several visitors.

Dr Salmond said: As you are aware, the subject assigned to this class is Mental Science— the science which has for its subject-matter the facts of niind. The dignity of the subject, you can see, admits of no question; but while its dignity cannot be denied, it must be admitted to be difficult and complex. But it has this consolation: it is full of gain and great reward to students who have natures attuned to it and apply themselves to it with sufficient assiduity. The subject is also very large; and although it is possible to put a great deal of work into six mouths, yet I scarcely know how to overtake it all even in that time. Therefore I intend to proceed at once with speed, and at the same time with deliberation and without unprofitable haste, to the proper work. I am going to take it for granted that I am dealing with those who know nothing about the subject, and who stand upon the threshold desirous of an introduction. It may be presuming too much, as some of you who purposed joining the class niay have occupied yourselves in preparation during the summer months, but I am going to make no account of that. Just as when we see some great building we are fain to first staud and gaze up at it to take in the general effect, then walk round to view it from the north, south, east, and west, and finally pass inside to be at leisure to survey it piece by piece; or as on taking up some new volume we are fain at once to turn to the table of contents and run it over, so we do here.: We first take a general hasty view of what the subject includes. It seems to me to include five main divisions, —psychology, logic, ethics, ' metaphysics, and history of philosophy. Looking at them in succession in a preparatory way, we begin with psychology. This word, by its Greek derivation, should be equivalent to mental science, and it is sometimes soused. In reality, though, it is now used in a narrower sense—viz., as a department within mental science. It is therefore that department of mental science which remains after excluding the other departments —logic, ethics, metaphysics, and history of philosophy. Meanwhile, leaving this out of sight, psychology has to do with the facts and phenomena of mind and intelligence. Every science must have a well-marked group of phenomena, each having points of association but railed off like natural specimens in a museum. These phenomena are in a kind of orderly confusion ; but we require to think artificial order into them and group them, and we do that ac- ' cording to certain well-marked affinities. It is important to remember this: that our divisions of science are artificial, not real; so that all sciences have affinities to each other and shade into and overlie each other, as it were, in uneven lines of division. But we can group the phenomena and make distinct branches of science : botany sand zoology, for example. .We can see that these are sufficiently marked off from each other at one point, yet they shade over into each other. So psychology has many relations to other branches of science and cannot sometimes be marked off, but has yet a group of its own..and is as .well, defined as any branch of thought. It is marked off by a wonderful fact— the self-conscious reason of man. Now, when we have marked off a branch of science, the first thing met with is ,a multiplicity and variety of unconnected facts exposed to view. The astronomer lifts his eyes to the heavens and sees a miscellaneous, unconnected mass of facts, and he gazes at the heavens until he thinks order into that confusion. The botanist looks into the vegetable world in the same way, and thinks order into it. So in psychology: we are met by a flood of miscellaneous facts. Let a man observe himself from awakening in the morning until retiring to rest at night: there has been passing through his mind an unceasing stream. The stream of self-cousciousness never stops for a moment—thoughts, resolves, desires, &c, —looking without and within all is disorder. Is there no order and law there ? Can we ■ not look into it until it resolves itself into order ? We find that we can, although 10,000 separate facts were in our thoughts to-day. We find that they fall into three groups—the intellectual, the emotional, and the volitional. That is, they are resolved into intelligence, emotion, and will. Thus we find the very suggestion of thought. We see a person in. the street. At once there rises to our recollection the last place we saw him in, then the person we saw with him, and so on. It is thought suggested at haphazard, but we can gaze at this fact until order is evoked. Take a mental fact like perception. We gaze at and see a certain object, note its size, shape, &c, and the process seems like intuition. But is it ? We gaze at it until this fact falls to pieces before our eyes, and we can see its genesis and how we learned to grasp ■.it. In this, as in other branches of science, we think order into facts. We come to this—we learn to know ourselves; and this brings the reward of all knowledge in all* departments—the conversion of a proud unconscious look into the gaze of clarified reason. You see before leaving this that psychology is an inductive science as complete as others, resting on the observation of facts; and we carry facts to it from all quarters in order to draw inferences. It rests also on experiments as far as applicable. We think the world of mind. Multiplicity disappears in the unity of reason; disorder vanishes as it is grasped by thought. We proceed in the same way in the second branch—logic. This has reference to specific mental functions, for which the most expressive and comprehensive word is—Reasoning. We not only form judgments and link them together, and doing this proceed to further judgments, but we prove and establish conclusions; explain, explore and define, and penetrate beyond the known to the unknown. A most simple example is to be found in the ordinary syllogism*" AH men are mortal; Peter is a uiaii." We link them together, and proceed to a judgment distinct from both. " Therefore, Peter is mortal." But there are other ways. A child puts its hand on to the bars of a grate and is burned. He does not do it again, because he takes it for granted that the same thing will happen again—that nature is uniform in its operations. ,In days long past, men observed that if a cellar were left shut up for a great length of time and a man went into it, he was known to fall down dead. Why was this? The ancients said it was on account of a mysterious animal, called a basilisk, which fixed its eyes upon him. But the prosecution of modern science tells us that the cause was an accumulation of carbonic acid gas; and in this way man proceeds to reason and infer from facts, causes. Now this work of reasoning, whether it proceeds inductively or deductively, is done instinctively. The mind does it as the stomach digests food and the lungs breathe—without conscious act or resolution—and there dawns on us that great fact that nothing can be more erroneous than to speak of the human miud as a blank sheet of paper. It is ab initio an organised thing—organised to perform certain functions, and it does so at once straight away. Why is this the case? We should like to understand the process. There logic begins to develop itself into a science. We pursue it not in order that we may reason, but in order that wo may reason better, and do by ratiocination what formerly we diet I.- . . :;.:ct. Not only

this, but we find that we) often perform reasoning processes very imperfectly and go wrong. Nothing is. more common than to hear a man reason that because all B is A, therefore all A is B. Nothing is more common than to hear wrong causes assigned to things—reasoning that

if a natural agent does so and so under certain conditions, it will always do the same. A man might just as well reason that because,one pill does him good, therefore seven pills will make him well seven times as fast. Therefore the question emerges, Ho ware we to learn to rea-

son perfectly ? Are there any rules or tests of right reasoniug and safeguards against wrong reasoning?—and there logic emerges. Logic is related to truth only instrumentally, and therefore both logic and mathematics are known as formal sciences. Logic does not provide a man with the matter of truth, but the processes. It tests the matter and tests the processes. This is important to remember. If you read, say, such an able writer as Newman, and hear him leading proofs—say "of the existence of an infallible church, —sometimes his reasoning is directed to the very great good that would accrue from the possession of such a church, and so on. Now logic has nothing to do with the matter of this reasoning, whether there is an infallible church or not? What logic does is simply to test the validity of the process of proving it. And all through logic has to do with form, and not matter. An important practical result springs from this. You may have observed that great disputers are more often wrong than other people. The reason is that they forget logic is only a formal instrument i and that the matter must be supplied, from other quarters altogether, and when they proceed thus in pure egotism to exercise logical forms the result is pitiable. It makes them mere beaters of the air. You must get the matter to which logic is to be applied from other quarters.

The third section which'comes under the head of mental science is ethics. Among the various facts of human reason we soon discover a cer-

tain class which are readily grouped by themselves, and are so important as to demand and receive separate grouping from us. These are

known as ethical facts. Man not only thinks and reasons, but acts—and acts not automatically, but rationally ami consciously. He consciously determines himself in the prosecution of aims and goes through the world saying " I will " and " I will not"; and a man's will is more emphatically himself than liis intellect. We say "My reason teaches me," and "My judgment decides," but we do not say "My will wills." We simply say " I will." A man's will lies in himself. It is his ethical self. To proceed: we discover as we awake to

rational self-cousciousuess that our will is nol

absolutely free. It finds itself confronted by law; and we are obliged in some way to relate ourselves to that law and come to terms with it.

If our will assents to the law and incorporates itself with it, we make a joyful discovery which expands and enriches our whole consciousness; but if we do not come to terms with that law, so far from becoming freer, our will becomes our own devil, harpy, and whirlwind. We discover that certain things must or should be done, and so actions are classed by us as good or evil. There thus emerges a class of most important questions. In what sense am I a self-determin-ing being ? Am Iso only as a vegetable may be said to be, which grows from within by inner spontaneity, or only as an animal which obeys its instincts, or as a stone may be supposed to be that believes itself free when flying through the air until it comes in contact with an obstacle that stops its flight ? Is this the sense in which I am self-determining, or do I affirm something else ? This is the question of freedom of will. Then comes the inquiry, By what principle are actions classed ? What places all these actions] under one head and all those under another ? That question is at the origin of our knowledge of moral distinctions. I am conscious in the presence of certain actions of a perfectly distinct feeling of moral approbation; what is the origin of it? These are ethical questions, and you can see that the importance of mental science and its difficulties culminate in ethics. All great writers upon mental science have recognised this fact. It is touchingly brought up by Herbert Spencer in his preface to his " Data of Ethics" when he tells us that he has had an eye from the beginning upon the construction of an ethical system as the crown of all his labours; and feeling the night closing in around him and that he is about to die, he chooses to publish his ethics in an imperfect form. It is the same in Spinoza's ethics— the elaborate speculations which he calls his ethics. It must be so. Here results are gathered up and tested. Having so explained in a generally descriptive way what ethics includes, I may interject a remark. You can see it would be legitimate to regard logic and ethics as subsections of psychology, for reasoning is a mental fact, and willing is a mental fact. But they are separated for a sufficient reason—on account of their great importance. If I wished to be very exact, I might say there are three divisions of pueumatology, and divide it into psychology, logic, and ethics. The only reason the two latter are separated from psychology is on account of their bulk and importance. We can make divisions in any!way that will best suit our convenience.

The fourth branch of mental science is metaphysics. It may have created surprise in the minds of some of you to hear this enumerated as the fourth division. The word metaphysics has often been used in the past as synonymous with psychology, or psychology has been used as covering psychology proper and metaphysics. Hamilton's lectures, for instance, are called his lectures on metaphysics; but you will find the elements of psychology and metaphysics are heaped together, and 1 hold this system to have been most injurious and confusing, and many prejudices against mental science have come from running the two together. I hold metaphysics to be distinct from psychology. It is difficult to give you an understanding of what I mean, because there is no agreement as to the sense in which they are employed even amongst those who distinguish metaphysics from psychology. But without formal definition, I will try in a descriptive way to give you an idea of what I mean. The first thing is to familiarise your mind with this thought: that there is a vanishing point in all powers of the human body and mind—a limit to the horizon of vision. This applies even to the sense of hearing. Hearing is dependent on the vibrations of the air. It is discovered that there is a range of vibrations within which alone sound is audible—that range being from 16 to 36,000 vibrations a second. If the vibrations fall beneath 16 to a second there is no sound, but perfect silence. If they are more than 36,000 to the second, there is again absolute silence. This is the limit thrown around our capacity of hearing. For another example: If a man takes a piece of ice.in his hand, by applying heat to it the ice becomes water. By the application of further heat it becomes steam, and by using a more potent agent it falls into two gases. These are dissolvable into molecules, and it is found that these infinitesimally small manufactured articles are strangely subtle in composition. • They are dissolvable into atoms, but no one ever felt or weighed an atom. It is hypothetical altogether, and the idea of the atom marks the limit beyond which it is impossible to go in physical inquiry. For another example: Nothing is so absolutely necessary as to affirm something to be eternal and self-existent. Let a man be an atheist, deist, materialist—what you will, from this no one can escape: that seeing something is, something always must have been ; for if not, whence came being? If being was caused by another, whence came that other? There is no escape— unfatliomable mystery as it is—from the affirmation of this fact; but this marks the limit at which we are summoned to halt. Metaphysics thus leads us to the vanishing point, and summons us to deal with ultimate facts and realities. This, however, is not the best way of presenting the subject-matter of metaphysics. I can:put it in an easier way. Supposing I say: "I see a house half-a-mile away "; what that says is: "I have a perception which I locate there in space." The idea of space seems to lie behind all my perceptions. Unless I had first'this idea of space, I could no more say I perceive a house than I could furnish a house without having a house to furnish. I find the idea of space is a necessary antecedent to thinking. But where did I get this notion ? Is space in objective existence ? If I and all else were to cease to exist, would there still be space left like empty room ? Science is constantly speaking to us as though knowing things in co-existence, and physical science never makes any account of space; it takes it for granted. But metaphysics does trouble its head about this subject. : It steps up and says " Explain it." Or again, supposing I say, "It happened to rain this morning," I fix an event in succession—before and after in time; I cannot speak without assuming it. But what is time, and how do I come to have knowledge of it ? Science is constantly speaking to us about knowing things in succession— cause and effect, &c, —but it takes the fact for granted. Metaphysics, however, steps in and says, " What about this thing time? What is its explanation ? " Or take another example: A person sees that cork swims, that iron sinks, and that an iron vessel floats ; and asks, Why ? ; Or a child, seeing a watch, puts it to his ear and says " Something caused this sound," and wants to look inside and see the cause of the ticking. Or a child lies awake in the middle of the night, and hearing a strange sound, is terrified if he cannot give an intelligible cause for it. If he can satisfy himself of the cause, he is quiet and rests. This idea of cause, then, besets us behind and before. We get the idea; but what is cause? Science is always inquiring into cause and effect, but it never troubles its head further. But metaphysics does. Inductive psychology looks at facts of mind, and is satisfied with grouping and giving them law; but metaphysics is not satisfied. It asks, What is this mystic ego that links and groups them all into its own consciousness ? Is there any real thing behind ? Thus science is always speaking about the relations of things to each other; but metaphysics steps up and says, " What1 is the meaning of this word Relation ? How did the mind get hold of it ? And how did the relations I think ever get in amongst things themselves ?" It comes to this : when we analyse the contents and operations of our minds we come at last upon certain ultimate conceptions which all men have and all men use, for the most part unconsciously—forming the horizon of vision. Metaphysics deals with this. It is therefore the science that deals with our ultimate perceptions—with our most general and comprehensive conceptions. It has therefore been properly called "philosophy par excellence," or also from the Greek—metaphysics— because it deals with things after and behind physics. So wo might say that there is a metaphysics of psychology, of logic, and of ethics. There might be metaphysical inquiry instituted in each of these branches, because each lands you face to face with an ultimate question. For example: Psychology deals with the laws of ■ memory and association of ideas, but metaphysics is not satisfied. It says, " This memory is a strange thing." When I say, " I who am

here now am the same person who wfcs in London 30 years ago," I link these years and years of facts into the unity of my self - consciousness. But can I trust this ? Am I sure of it ? Can I really trust this fact of personal identity? Logic again gives you the marks of a sound syllogism, or the degree of certainty to attach to auy dstinction; but metaphysics probes further, and wants the grounds for taking for granted the uniformity of nature and the idea of cause. Ethics is content to trace the origin of moral distinctions and the analysis of conscience, but metaphysics inquires into the nature of moral personality and the final cause of human existence. There is much illwill at present against metaphysics; but you observe the mind of man cannot do without it, and most of those who inveigh against it are found inveighing against it with very bad metaphysics of their own. But metaphysics is very subtle and difficult, so you should not begin with it. The great evil with many students is their impatience ■to start metaphysics. You should carefully wade through the other branches, and then you will be in a better position to grapple with its difficulties. The method of dealing with it is peculiar—observation, experiment, of induction are of no service; there must be a legitimate speculation, or a legitimate dialectic, or there can be no such thing as metaphysics. The fifth and last branch is " history of philosophy." Properly this should be "history of mental science," and should include, the history of all the branches—psychology, logic, ethics, and metaphysics. But it is for the most part the history of metaphysical speculation, for the reason that nine-tenths of mental science in the past has been of that nature. It is strange that this expression "history of philosophy" is the only case in which we use the word "philosophy " as the Germans use it—viz., as equivalent to metaphysics. Generally we use it wherever and whenever we wish to indicate that auy sort of activity rests on or is guided by reasoned principles. We see over shop windows "Philosophical instrument maker," and even announcements that hair is cut or trousers made "on philosophical principles." It merely means that the man is going to apply some exact knowledge or principle to the work. To resume: Mental science in all its branches has had a history, and it can only be understood properly in the light of that history. As Julius Ca3sar would be unintelligible without Marius and Sulla; as Aristotle is dependent upon Plato and Plato upon Socrates; as without a Hume there could never have been a Kant, and without a Kant there would never have been a Hagel—so we read the history of philosophy. There are various verdicts as to its value. According to some it is a melancholy story of vain and misdirected effort—showing how men have been all along pursuing a will-of-the-wisp. On the other hand, to me it seems one of the sublimest stories—

the story of the earnest efforts of the sublimest minds that ever adorned the human race, and full to the student of quickening inspiration.