Elements of logic, together with an introductory view of philosophy in general, and a preliminary view of the reason. By Henry P. Tappan

Front matter

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Preface

The work here undertaken differs somewhat in its scope and design from systems of Logic which have hitherto been given to the world. The Aristotelian Logic is simply the method of deduction ; and, as such, it is complete. Subsequent works, in so far as they have been strictly logical, have closely copied the great master, and have confined themselves to an exhibition of the deductive principles and processes. Now, the deductive method comprehends merely the laws which govern inferences or conclusions from premises previously established. These premises may, in their turn, be inferences from other premises, and so on, to a certain extent ; and just so far this method is all sufficient. But it is evident that the evolution of premises and conclusions, and conclusions and premises, must have a limit. There must be premises which are not conclusions from other premises, but which arise in some other way. Now, a complete and adequate

PREFACE.

Logic ought to exhibit this other way likewise : it ought to inform us how the most original premises arise, and upon what basis they rest.

Other methods, indeed, have been abroad in the world, but without being systematically propounded as parts of Logic. Thus, the Platonic philosophy really contains a Logical development of the most original forms of human thought, springing out of the intuitive faculty. And the Novum Organum of Bacon contains a logical exposition of the method of establishing first principles through the observation of phenomena.

Both Plato and Bacon have had many able disciples and expounders ; and both are daily coming out into a broader and clearer light, not as opponents, but — to adopt the thought of Coleridge — as the opposite poles of one great and harmonious system.

The present attempt, therefore, is to make out the system of Logic under its several departments ; and to present it not merely as a method of obtaining inferences from truths, but also as a method of establishing those first truths and general principles which must precede all deduction.

With all humility, I acknowledge my indebtedness to the great thinkers who have preceded me. I have of course read as well as thought ; and my thinking and reading are naturally blended together. With this acknowledgment, may I be permitted to go on with my work, without stopping to note nar-

PREFACE. 5

rowly in my own mmd, or to remark to my reader, when I am drawing from original, and when from other sources? I ought, perhaps, in justice to myself, to remark, that the entire plan of this work was struck out several years since, and different portions of it written before Professor Whewell's and Mr. Mills' elaborate and suggestive works had fallen under my eye.

That Logic really embraces all the parts which I have assigned to it, I think will fully appear in the sequel. It is that branch of philosophy which expounds the laws of the Reason as the faculty of truth and reality.

The view which I have taken of Logic, will justify the prolegomena. I give the Introduction to Philosophy in General, in order to point out the relative position and importance of Logic in a philosophical system. And I give the Preliminary View of the Reason, because, since this is the faculty which reasons, or logieizes, I deemed that such a view, if given both clearly and briefly, would be satisfactory in this place.

Part I. Introductory View Of Philosophy In General

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Section I. — Definition of Philosophy 15 II. — Distinction between the Phenomenal and the Metaphe

nomenal 23

III. — Of the Reality of the Metaphenomenal 27

IV.— The Objective and the Subjective 32

V. — Reason and Sense 39

VI. — Sensualism and Transcendentalism 42

VII. — Ideas and Laws 50

VIII. — Primary and Secondary Phenomena 58

IX. — Antecedence in Time and in Necessary Existence 60

X. — Ideas the last Authority of all Judgments or Knowledges .... 64

XI. — Divisions of Philosophy

I. Metaphysics 70

Comprehending

Psychology 71

Dynamics 73

Anthropology 74

Ontology 75

II. Nomology; comprehending

The Morale 80

Esthetics ib.

Somatology 82

Logic. ., 83

8 CONTENTS.

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Sect. XII.— Of the Relations between Philosophy and the Sciences and

Geometry 89

Sciences of Discrete Quantity 91

Natural Science 92

Conditional and Unconditional Science 95

Art 99

XIII. — Reason, the Organ of Philosophy 103

XIV.— Criteria of a True Philosophy 108

Part II. Preliminary View Of The Reason

Section I. — General Introductory Considerations respecting the Reason... 123

II. — Outline of the Ideas and Functions of the Reason 129

III. — Explication of Ideas 138

IV. — Explication of the Functions of the Reason 143

V. — Does Logic comprehend all the Functions of the Reason?.,., 144

Book I. Primordial, Logic

Section I.-r-General Laws of the Evolution of Ideas 148

II. Metaphysical Ideas ; comprehending

I. Subject and Objeotive Exteriority 155

II. Time and Space 156

III. The Infinite and the Finite 159

IV. Quantity ib.

V. Quality 165

VI. Relation 167

VII. Modality 172

III. — Nomological Ideas; comprehending

L Law 177

CONTENTS. 9

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II. Matter and Spirit 178

III. Perfection ib.

IV. Right and Wrong. 180

V. Freedom and Responsibility 182

VI. Personal Identity 183

VII. Immortality 184

VIII. The Beautiful, comprehending

Symmetry 187

Grace 188

Regularity, Uniformity, Variety ib.

Determinate Form 189

The Sublime 190

Melody '. 191

Harmony ib.

IX. The Useful 196

X. Centralization and Diffusion 198

XL Affinity and Repulsion 199

XII. Life ib.

XIII. Polarity 200

XIV. Instinct 201

XV. Regularity, Uniformity, Variety, Symmetry, and

Determinate Form 202

XVI. Identity, Difference, Resemblance 203

XVII. Design, Final Cause, Means and End 205

XVIII. Truth 207

XIX. The Philosophical Idea 209

XX. Intuition 210

XXI. Involution and Evolution 211

XXII. Analysis and Synthesis 213

IV. — Primary Sensuous Cognitions, or Cognitions of the Exterior

Consciousness 219

V. — Primary Subjective Cognitions, or Cognitions of the Interior

Consciousness 222

VI.— Axioms 224

Metaphysical Axioms 226

NOmological Axioms 228

VII. — Of the Characteristics of Axioms in general . 235

VIDI. — General Relations of Axioms 240

IX.— Definitions 243

10 CONTENTS.

Book II. Inductive Logic

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Section I. — Introduction 249

II. — Causes and Laws 252

III. — The Human Reason, as related to the Objective World 259

IV. — General View of Classification 262

V. — Principles determining the Induction of Phenomena in Classification 265

VI. — Distinction between a General Fact and an Absolute and

Fixed Law 276

VII.— The Logic of General Facts 283

Principles of Elimination :

I. General Difference with Uniform Agreement in One

Point 288

II. General Agreement with Uniform Difference in One

Point 289

III. Elimination by Corresponding Quantities and Inten-

sities 291

IV. Elimination of the Terms of a Sequence, in order to

determine which is the Antecedent and which the

Consequent 294

VIII. — Inductive Logic of Universal and Necessary Laws 303

IX.— The Logic of Art 315

BOOK III. deductive logic.

Section I. — Introduction 318

II. — Analysis of Propositions 320

III. — Of Propositions, as opposed to each other 325

TV. — Of the Conversion of Propositions 328

V. — Propositions constructed into Syllogisms 332

VI.— Of Moods and Figures 347

VII.— Of the Reduction of Syllogisms 351

VLTI. — Of Modal, Hypothetical, and Disjunctive Propositions 354

IX. — Hypothetical Reasoning 357

X.— Of the Dilemma 362

XL— Of the Sorites 365

XH. — Application of the Deductive Formula 368

CONTENTS. 11

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Sec. XIII.— Of Fallacies.

Fallacies of Deduction 377

Comprehending

I. Fallacies in the Formula 378

II. Fallacies in the Matter 380

1. Ambiguous Middle ib.

2. Fallacies relating to the Connection between the

Matter of the Premises and that of the Conclusion. 383 Fallacies of Induction ; comprehending

I. Fallacies of Observation 393

II. Fallacies in Determining General Facts 396

III. Fallacies in Inducting Laws 398

Fallacies in respect to Intuition 399

Book IV. Doctrine Of Evidence

Section I.— Nature of Proof. 403

II. — The different kinds of & priori and a posteriori Proof. 408

III. — Of the Nature of the Relation between Antecedents and Consequents 413

IY.— Of Degrees of Evidence 416

V.— Of Testimony 430

VI. — Circumstantial Evidence 436

VII. — Argument from Progressive Approach 443

VIII. — Proving by Example 446

IX. — Reasoning from Experience 451

X. — Reasoning from Resemblance and Analogy 454

XL — Demonstrative Proof. 462

XII. — Calculation of Probabilities and Chances 463

Part I. Inteoductoky View Of Philosophy In General

PART I.

INTRODUCTORY VIEW OF PHILOSOPHY IN GENERAL.

SECTION I.

DEFINITION OF PHILOSOPHY.

The term Philosophy in common usage has obtained an indefinite and often an improper application. When employed alone, and without relation to any specific subject, it is generally supposed to refer to natural science : and thus a Treatise, or Essay, or Lecture, on Philosophy, would be expected to embrace something relating to Mechanics, Astronomy, Chemistry, Electricity, or Magnetism.

Some undoubtedly would go beyond this ; and regard the term in its higher applications, as expressing something in relation to the doctrines of the intellectual and moral powers : or they would simply identify it with Metaphysics, a term no less vague and obscure to common apprehension.

It is to be expected that the affirmation will at first appear to many paradoxical, that Mechanics, Astronomy, Chemistry, &c, are not branches of Philosophy : but in the end it will appear perfectly just. Philosophy indeed holds a close and most important relation to these sciences : they are grand results of philosophy ; but they are not philosophy itself. And even Metaphysics, general and comprehensive as it is, does not comprehend all philosophy — it only forms one of its important divisions.

In defining philosophy, we may go on to say, that it is the Scientia Scientiarum — " the Science of Sciences ; as its object is to explain the principles and causes of all things existing ; and to supply the defects of inferior sciences, which do not demonstrate, or sufficiently explain their principles/' * Or we may call it the " Science of the Universal and the Absolute." But this is not enough. It would be like defining Astronomy as the " Science of the Heavens." A definition may be just, and yet by reason of its dry, general, technical, and elaborate form of expression, may fall short of the true end of all definition, viz., to lead the intelligence to a clearer insight and a more perfect comprehension.

Philosophy is a word formed from the Greek $£koao- $>ia. It primarily expresses a mental affection — a love of knowledge or of wisdom.

It cannot be questioned that such an affection is inherent in the human mind. It appears in feeble infancy — it stimulates the activities of the busy prattling child — it forms the wakeful earnestness and joy of youth — it stirs nobly in manhood — it decays not with the decay of age. It is a moving spirit even in savage life, and shows man, when lowest, as still above the brute. This impulse to know, this restless curiosity, is connected with the whole development of humanity in Science, Arts, Government, and Keligion. Co-existent with this love of knowledge is the love of external action. Hence, the development of humanity appears not only in the cultivation of the intelligence and the consequent unfolding of the sciences ; but also in the construction of implements and machinery, and

* Ed. Ency.

in the changes and improvements wrought upon the face of Nature. The eager love of knowledge, and the no less eager love of action — the impulse to know, and the impulse to do— these are elements spontaneously at work in human nature, and may be appropriately termed philosophical elements.

Let us conceive of that period when the Heavens and the Earth were finished, and man was created and placed in the Earth its inhabitant and lord. Then he had the same faculties which he now possesses ; and the Earth was under the government of the same physical laws which govern it now ; but his faculties were undeveloped, and science and art had not yet appeared ; and the Earth, whatever modifications it might be capable of, stood as it came from the hand of the Creator, in uncultivated beauty. But man, as he walks abroad upon the Earth, with all the endowments of intelligence and feeling, observes the Heavens and the Earth, exercises thought, generalises, and forms conclusions. What is working within him, impresses its form upon all outward things : — the forest is levelled, and cultivated fields appear ; the mountain and the valley feel the touch of his hand, and put on new appearances ; he opens a way across rivers, and covers the ocean with fleets ; where rivers are wanting, he creates them ; he digs into the crust of the Earth, and brings up minerals and appropriates them ; he calls into being a thousand useful arts ; he scatters over the face of the Earth convenient habitations, and crowds them together into cities. But not only does he change the face of the Earth, and put to his uses its various materials — he also establishes government, administers law, and awards justice : he speaks eloquence into being ; poetry born in his heart, is expressed in flowing numbers ; he perfects sound into music ; he takes the chisel, and from the marhle quarry spring up forms whose beauty is divine ; and majestic temples, which seem born with them as their fit habitation ; he takes the pencil, and dipping it in the colors of heaven, imitates every form of life, and advances beyond Nature herself : he affirms, reasons, and believes ; draws out pure abstractions from his thought ; advances into Nature, and searches out laws for her phenomena ; and thus builds up systems of science : he invents a method of analysis, and, in the laboratory, compels Nature to reveal her more secret processes ; and, not content with this world, the light of heaven, which has lighted him to his labors here, he seizes upon as his minister, and makes it reveal to him the worlds from whence it has travelled. Still more — from these finite forms, he ascends up to the Infinite ; he is a worshipper of God, and an expectant of immortality.

" Imagine a being who had been present at the earliest days of the universe, and of human life ; who had seen the external surface of the Earth, as it came forth from the hands of Nature, and looked upon all the beauty of those ancient times ; who had seen the beautiful forms which Nature presented, and heard the melodious sounds which she then uttered ; in a word, a being who had been a spectator of the first exhibition of the primitive world, and who should return at the present day amidst the prodigies of our industry, our institutions, and our arts ; would it not seem to him in his astonishment as if he no longer recognized the ancient dwelling-place of man ; as if beings of a superior order had transferred their abode to the Earth and had metamorphosed it ? " * Or contemplate an

epitome of the whole mighty development of mind in a single individual, appearing first on the shore of this world a feeble infant, and in less than a century assuming the character of a Newton, a Leibnitz, a Milton : and as an illustration of the changes made in the condition of the world by human invention and skill, take the history of Mechanics, of the Needle and the Telescope.

In contemplating these developments and changes, what enquiry springs up, yea, irresistibly springs up, in the mind ? Do we not ask, how all this came to pass, and why the developments and changes came up under these particular forms 7 Do we not ask, why did man change the face of the Earth ? Why did he create government 1 Why did he give birth to science and art ? Where and how did the development of his mind begin ; and how did it proceed? What are the laws of his thought, the ground of his knowledges and beliefs, the forms of his reasonings, and the methods of his investigations ? What are the laws of his emotions and passions ? What are the capacity and force, and what the laws of his will ?

Enquiries like these evince the workings of the philosophic spirit ; they are found under some form, in some degree, in every human mind. Few, indeed, take in that whole field of enquiry, which embraces the complete development of humanity ; but whether in the child, or in the adult, in the savage, or in cultivated man, you perceive questionings after the origin and reason of things — after efficient and final causes — an earnest prying of the mind into something beyond mere visible and tangible forms, you there perceive the workings of the philosophic impulse — the $L\o(ro<f>ia. This is the dawn of philosophy. The impulse to know and to do, the elements of philosophy spontaneously at work in the mind, lead forth the developments and changes above mentioned. The enquiry after the causes and reasons of these developments and changes, after they have in any degree taken place, is the higher form of the <PiXoao<f)ia, and leads forth the mind to the construction of philosophy as a system. Under the first form, the mind appears intent upon its objects, thinking, feeling, doing, and making its inherent energies to appear in external effects. Under the second form, it turns back upon itself, — that is, makes itself its own object by an act of reflection, and finds out its own reach and limits, its own aims and laws.

<f>i\oao$la, from expressing the impulse to know and the consequent causal activity of man, and from expressing, after the development of humanity has taken place, the impulse to seek after the laws and principles which have governed this development, comes to express these laws and principles themselves. These laws and principles, like the simple desire of knowledge, act spontaneously in the development of humanity. They are in the highest sense philosophical elements of our being, inseparable from it, and energizing as a plastic power within, and as such distinguishable from philosophy as an expressed system without, laid down in books, or in the lectures of the schools. The first, of course, gives birth to the second, as thought gives birth to language.

In that early period of humanity to which we have adverted, it could not exist as a developed system : it was then in man as a light and a power, under which he thought and acted, but upon which he did not reflect : Thus the idea of the useful, led him to change the face of nature and to originate the ordinary arts : The idea of justice, led him to constitute government and law : The idea of the beautiful, led him to the creations of painting, sculpture, music, and poetry : The inherent laws of Ms intelligence, guided him in his reasonings ; he believed, because he could not disbelieve, and faith appeared in him like a sublime and divine instinct : When he looked out upon the phenomena of the world, he assigned them causes, because he could not think of "them without this relation : And from finite being, his mind necessarily rose up to the conception of the Infinite Being — he became a worshipper under the energy of a spontaneous and irresistible idea.

At length reflection began — when it began we know not, but its beginning was the birth of philosophy as a system developed and recognized. By the act of reflection, or self-consciousness, the mind turns back upon itself, and makes itself the object of its own contemplations. All the phenomena of the mind, are presented in the field of its consciousness ; — the sensations which are caused by the external world — the affirmations of the reason — the volitions— must all alike appear there, in order to be known. There is an ordinary consciousness which belongs necessarily to every man ; but reflection is a special and voluntary consciousness, and thence called a philosophic consciousness, which appears only when the mind becomes the object of its own observation by an act of self-determination.

Now in the exercise of this philosophic consciousness, the mind questions itself respecting the grounds of its knowledge and its faith — respecting the forms of its thinking, and the modes of its investigation — respecting the grounds of its decisions in arts, morals, government, and religion : it makes those very enquiries which we recognize in ourselves, when, reviewing the progressive development of humanity, we are struck with wonder and admiration at what man has accomplished, and at what man has himself become. The results of these enquiries form systematic philosophy.

Let us sum up here the preceding observations, so as to present a succinct definition.

1. Philosophy, from $t\oao<f)ia, expresses the inherent desire of knowledge in the human mind ; and as closely connected with this, the desire of action. Under the impulse of these desires man begins to acquire knowledge ; and to exert his causality in appropriating the materials supplied him from the earth — in working in various arts, and in modifying the face of nature.

2. After a time he begins to reflect upon the development of his mind, the facts he has observed, and the works of his own power and skill : and now the QCkocrofyia, or love of knowing, takes a new direction, and impels him to search out the causes, laws, and forms of the various development of his own being.

3. These causes, laws and forms really existed subjectively, inseparable from himself, before he began to make them the object of his thought and curious inquiry : and they, as the first principles of his being, and as governing its manifestations, are the substantial elements of philosophy,

4. These first principles of his being are known through reflection, or self-consciousness ; and when stated methodically, under proper divisions, and with clear definitions and expositions, form Didactic Philosophy.

The term $i\oGo$ia, which at first expressed only the desire of knowledge, or love of truth spontaneously working in the human mind, is thus employed to express all the grand results of this high and glorious impulse.

Section II. Distinction Between The Phenomenal And The Metaphenomenal

Consciousness is the common field of all our mental activity. All our sensations, our perceptions, thinking, and reasoning, our imaginations and fancies, our emotions, passions, determinations, and volitions, alike appear, and are recognized here. These affections of our being are not the movements of an insensate mechanism : we know them in their going on, and we know ourselves as the subjects of them.

Now there is an important distinction to be drawn here. The distinction between the immediate objects of consciousness, and those objects which, although known, or at least supposed to be known, yet lie without the sphere of consciousness. The immediate objects of our consciousness axe phenomena, and these only are phenomena ; while those objects which, by supposition, lie beyond immediate consciousness, are metaphenomenal.

"What are the immediate objects of consciousness, or of what are we immediately conscious ? This is the first enquiry.

Let us begin with our sensations. The sensations are affections of our inner being, and unquestionably are the immediate objects of consciousness. But there are many perceptions and judgments which come up to view in connection with the sensations, which, together with their objects, are entirely distinct from trie sensations. The bare sensations are those of color, of sound, of fragrance, of taste, of touch, of heat and cold, of titillation, and of pain and pleasure. In these are contained what are commonly called the secondary qualities of matter : but this designation cannot be made from the bare sensations. We have in the sensations mere internal experiences, or movements of our own inner being. We are not conscious of matter, distance, space, substance, or cause ; — we are conscious of sensations only. We may be conscious of the action of other faculties of our being, affirming or perceiving the existence of body, distance, space, substance, and cause ; but the bare sensations are no such affirmation, or perception. I think it must be plain to every mind that will reflect a little, that if we had only the sensations above mentioned, we should have no knowledge of an external world whatever.

The same conclusion must be drawn with respect to the primary qualities of matter. These are extension and resistance. But resistance to immediate consciousness is only an internal experience, and extension only a repetition of this experience. There is nothing in this experience to give us a knowledge of any thing external : time, space, substance, and cause, are not contained in a mere inward experience, a mere modification of our own being. In the primary qualities, therefore, we have no immediate consciousness of an external world. It thus appears, in general, that we have an immediate consciousness only of certain affections or modifications of our own being. What immediately appears to us, what we immediately know, are these affections. These are truly the phenomenal. If there be an external world, — if there be substance, space, time, and cause, — they are not phenomenal, or immediately recognized in the consciousness, nor do they come directly from the sensations.

Let us suppose, then, that we have faculties by which we can know an external world, and by which we can know substance, time, space, body, and cause, either through the sensations, or independently of them ; then, with respect to these faculties, the enquiry arises also, what are the immediate objects of consciousness ?

The faculties themselves are not the immediate objects ; nor are the objects perceived, and the truths affirmed, the immediate objects : simply the acts of these faculties are the immediate objects of consciousness. Thus in perceiving any external object, as a house or a tree, I am not immediately conscious of the house or the tree, but of sensations of color, and of the act of perceiving. The external object does not come into my consciousness, but only the sensations and perceptions, and these are simply movements of my own being. Indeed, my own being, as a substance endowed with faculties of feeling, knowing and willing, is not immediately presented to my consciousness : I am conscious only of certain phenomena, and of acts of judgment connecting the phenomena with external objects and internal faculties.

In processes of deep thinking and reasoning, the same holds true. In studying out some mathematical theorem, for example, the recondite mathematical relations, — the necessary and absolute truths are not immediate objects of consciousness ; — but the acts of attention, the acts of thinking and reasoning — the modifications of my own being in order to know and comprehend, and in knowing and comprehending. The mathematical relations, the necessary and absolute truths, do not come into consciousness as phenomena, — the acts and modifications of my own being are the phenomena, while the relations and truths are metaphenomenal.

Again, God is invisible : He is neither as a substance addressed to the senses, nor is he manifested to the consciousness as a modification of our interior being ; but still, if known at all, he must be known by these modifications : He is not the phenomena of consciousness, but known througli them.

Here, then, we have the broad and clear distinction between the phenomenal and the metaphenomenal. Sensations, emotions and passions, acts of perceiving, judging, reasoning and imagining, acts of choice and volition — these, as the immediate objects of consciousness, are phenomenal ; but the causes of sensation, emotion, and passion, the objects and truths perceived, affirmed, or deduced, the objects of the imagination, of choice and volition — these, not being the immediate objects of consciousness, are metaphenomenal.

Section III. Of The Reality Of The Metaphenomenal

The reality of the phenomenal is not questioned. That I have certain sensations, perceptions, emotions, passions, and volitions, this is immediate knowledge and consciousness : but whether the objects of these acts and experiences of my being have a real, positive, and independent existence, this may be and has been questioned, and even denied : The reality of the metaphenomenal has been questioned and denied.

It will be readily granted by all, that by the imagination we can create objects which are unreal ; and that in our actual perceptions we are often mistaken, and seem to perceive what we afterwards discover to have no reality, or to be a very different object from what we thought it to be. But, beyond all this, it has been contended that there is no objective reality whatever ; — that the tree and the house which I now see, and which everybody sees, has no existence out of, and independently of, the perception of which I and everybody are immediately conscious ; and the same of all objects, whether external things, or internal truths.

It is undeniable that men generally believe in the reality of the metaphenomenal ; nay, that only a few speculative philosophers, have ever denied it.

Now, the aim of philosophy is to explain the actual development of our being, of all that man has thought and done. Hence even the errors of man must be explained. If, therefore, men have erred in their belief in the reality of the metaphenomenal, it must be shown both that it cannot exist, and how men have come to entertain this universal but erroneous belief.

Those who believe in the reality of the metaphenomenal are indeed required, as philosophers, to show, how it is legitimately attained : but, on the other hand, those who deny this reality, in opposition to a common sentiment, are justly required to explain this common sentiment.