There are few employments of life in which it is not sometimes advantageous to pause for a short time, and reflect upon the nature of the end proposed.1 The pursuit of knowledge is one of those in which this occasional relinquishment of the field of action for that of meditation, is especially needed. We enter upon it at a period when the feelings are quick and ardent, when the desire of distinction is strong, and when many amiable feelings of our nature, the personal affection which we owe to our dearest friends, and the reverence which seems almost to be due to their very opinions, impel us to engage with eagerness in a task which the all but universal consent of mankind has pronounced to be useful and honourable. There is not one of these motives of which I would desire to weaken the force. But valuable as they are as incentives to exertion, they obviously constitute an incomplete ground for any systematic devotion of our maturer powers. The claims of the pursuit of science, like all other claims with which we are concerned, must ultimately rest upon some intrinsic excellency or special suitableness of the object. Qualities such as these can alone give to it an enduring title to our regard. I design, upon the present occasion, to consider the claims of science in the light of the principle just stated. More especially, I wish to direct attention to the ground of those claims, in the immediate or implied relations of science to human nature; in its relations, namely, as an answer to some of the distinctive wants of the human mind, an exercise to its faculties, a discipline of the character and habits, [and] an instrument of conquest and dominion over the powers of surrounding Nature. In the present divided state of public sentiment, particularly in this country and with reference to this institution, there seems to be need of such a discussion; need also that it should not shrink from occupying the whole field of the inquiry. To ourselves at least it cannot but be useful to endeavour to form an intelligent conception of what is really implied in the pursuit of science, of the spirit which that pursuit demands, and of the ends to which it points. It is proper to state in the outset, that under the term Science, I include all general truths, discoverable by the human understanding, whether they are physical truths relating to the material universe, or moral truths relating to the constitution of our own nature, or truths of any other kind. And the order which I design to pursue is the following:
First, I shall consider the origin of scientific knowledge as respects both its internal and its external sources, and shall briefly examine the nature of its conclusions.
Secondly, I shall, from the previous inquiry, endeavour to draw a just conception of the relations of science to the constitution and design of our own minds, of the benefits which we owe to it, and of the corresponding claims which it possesses upon our regard.
I remark in the first place that all scientific truths are founded upon the observation of facts, that experience though not the only element, is yet an essential element of their existence.2 The truths of the natural sciences, as of astronomy, or optics, or electricity, are made known to us by the observation of natural phenomena, and by reflection upon the results of that observation. Nor can our knowledge of them be derived from any other origin. Thus every science is, as to its actual progress, a gradually increasing system of knowledge which, beginning with experience, advances ever onward through successive stages towards that perfection which no science has yet reached, which none perhaps ever will reach, but of which the idea becomes clearer and brighter, with every approach that we make. And although in this gradual progress of a science, the necessity for continued observation may become less and less urgent, although in some instances it may even altogether disappear, yet, in every case, it must have supplied the first point of departure. This doctrine which is now so fully acknowledged that to dwell further upon it would be superfluous, did not always meet with acceptance. There was a time in which the indispensable necessity of a foundation in experience for all our knowledge of Nature, was not recognized. Among the ancients it was very imperfectly understood; during the long reign of scholasticism it was all but entirely ignored. And obvious as the principle in question appears to us now to be, it has won its way to general acceptance only through difficulty and opposition. It formed, indeed, with its more important consequences, the chief result of that great review of the sources and the methods of human knowledge, which we owe to the illustrious Bacon.3 But if science begins with experiment and observation, it does not end with them. All the knowledge which the senses have ever communicated to man, has been a mere collection of facts; and were there in the human mind no powers beyond those to which the senses make their direct appeal, that knowledge would never have advanced to any higher condition than that of facts. With such a state of information, however, the mind does not rest satisfied. It feels the pressure of impulses, it is conscious of the existence of powers and faculties which urge it to reduce the scattered details of its knowledge into form and order. It begins to compare and to classify, and to arrange. It examines in what respects different facts agree, and in what respects they differ; and it inquires how far those differences and agreements are constant; how far they are the results of circumstance or accident. Thus, from the contemplation of facts, the mind rises to the perception of their relations. While in the former stage it is little more than a passive recipient of the impressions of the external world, in the latter it exercises an unborrowed activity. The faculties of judgment, of abstraction, of comparison, [and] of reason, are an agency of strength and power from within, which it brings to bear upon the lifeless elements before it, shaping them into order, and extracting from them their hidden meaning and significance.
Thus, to take one department of human knowledge. It is not enough to have observed the courses of the heavens, the sun and moon, those greater and lesser lights, or that silent and countless multitude of stars, which, as soon as the light of day is withdrawn, unfold before us the true amplitude and grandeur of the material creation. Neither would it be enough, if every phase of apparent change which has swept across the heavens from the beginning of time until now, were recorded for our information. We desire to understand the nature of the phenomena which we survey. We would know how far appearances correspond to realities. We would ascertain the law of that “mystic dance”; we would unveil the secret mechanism of causes which produces the order that is seen, and makes that order perpetual.4 Impatient alike of unconnected and of causeless phenomena, we would reduce all that we behold around us into subjection to our own understandings. And the frame of nature is so constituted as to permit us in a great measure to accomplish that which we desire. If we are conscious of desires and impulses which cannot rest in the possession of particular and solitary facts, but find only in the contemplation of general truths, of constant and predominating laws, their corresponding goal and end; there is in the constitution of nature that which may answer those desires and satisfy those impulses. If we are sensible of the existence of faculties and powers whose province it is to detect order amid apparent diversity, to discover the indications of cause amid the seeming results of accident, those faculties do not exist in vain. The mind of man is placed amid a scene which can afford to all its powers their appropriate exercise. There is thus a correspondency between the powers of the human understanding and the outward scenes and circumstances which press upon its regard. In this agreement alone is Science made possible to us. The native powers of the mind, cast abroad amid a world of mere chance and disorder, could never have realised the conception of law. On the other hand, the fairest scenes of order, and the most unbroken sequences of causation, would have unfolded themselves in vain before a mind unpossessed of those higher faculties which are necessary to their apprehension. The actual circumstances of our position afford us at once the fairest field of exertion, and the surest guarantee of a success proportioned to the diligence of our labours.
I have dwelt upon this view of the nature of science, because I think it important to our present inquiry that its twofold origin should be fully recognised. If, before the time of Bacon, the external sources of human knowledge were too little regarded, we may, in the strong reaction of a subsequent age against this form of error, discern, perhaps, too much of the contrary tendency. Science, in its actual development, may indeed be compared to some stately temple, whose materials have been brought together from many distant regions, some from the forest, and some from the mine and quarry, but in whose fair proportions and goodly order, we read the traces of the designing mind.5 To all just theory, experience and observation are indeed the necessary prerequisites, but it is the intellect of man operating by laws and processes of its own, which executes the scheme. To those laws and to those processes there belongs an interest quite independent of the results of material science to which they give birth; and for this reason they deserve a distinct attention. But it is only when the two studies, the material and the mental, are associated together, that the true relations of science to human nature are recognised. Then it is that in studying the laws of external nature, a light is shed upon our own, which may seem to us even of more value than the source from which it is derived.
We have examined the sources from which scientific knowledge is derived. Let us inquire, in the next place, what are the most general conclusions to which it conducts us, with reference to the constitution of the universe.
Science exhibits to us the material or physical universe as a system of being, subject, in all respects, to the dominion of fixed and invariable laws. In that system, to the utmost extent to which either the observations of sense, or the deductions of reason, permit us to judge, chance and accident have no place. The condition of its existence is a rigid, unchangeable, necessity. All its successions are uniform; from its settled order, no deviation is either actual or possible. The courses of the stars are justly said to be appointed; “the sun knoweth his going down.”6 Yet in the conception of this rigorous and dominant necessity, repellent as it would be to our own natures, we see nothing to shock or to offend when viewed in connexion with the idea of matter. If the courses of nature are settled, they are settled in a consistent harmony. If her laws are so fixed that they cannot be broken, they are so fixed in themselves, so fixed in relation to the wants of sentient and intelligent beings, that regularity and beauty are the most conspicuous features of the world over which they preside.
Thus in the most ancient and most perfect of all the physical sciences, Astronomy, we contemplate not a particular orb or system, but a universe of worlds preserved in their mutual order and relation, through the agency of a single prevailing law. We trace the operation of that law in the most diverse consequences. We see it moulding the drops of rain, guiding the stone thrown from the hand in its course, and regulating the swing of the pendulum. We trace it in a larger circle of operations, renewing the waters of the ocean by the healthful play of the tides, deflecting the moon in its orbit, moulding the forms and determining the motions of planetary worlds, larger, and it may be, fairer, than our own.7 We are taught by the conclusions of analysis, that this law of gravitation has not merely a governing, but a preserving, agency; that it not only determines the motions of the whole system, but so determines them, as to provide for their stability and perpetuity. And beyond the confines of this system of ours, beyond the reach of the unassisted eye or thought of man, science still reads the indications of the same power. The faint lustre of spiral nebulae, and the calculated orbits of double stars, tell us of mightier revolutions, accomplished in obedience to the self-same guiding law.
Or to take a more special illustration of the necessity which governs external nature. A comet suddenly makes its appearance in the heavens. Whence it has come we know not, but we are acquainted with the general laws by which its motions we directed, and know the particular influences to which in this our region of space it must be subject.8 Three, or, at the most, five exact observations of its position, enable us to apply our knowledge to the determination of its actual motion; or could we by a single observation ascertain its exact place and direction, and velocity, at a given moment, the same end would be accomplished. The future path of the erratic stranger is then marked out, among the constellations. And the course thus assigned to it, it is actually observed to follow, until it again becomes invisible by its remoteness. Here we behold the dominion of necessity. Law is obeyed without choice or alternative. There is no deviation, no shortcoming, no excess. In the more recent and less perfect of the physical sciences, we have similar intimations of the nature and character of the material system. We have no reason to think that the law of definite proportions in the science of chemistry, or the laws of the connected agencies of light and heat, of magnetism and electricity, so far as they are actually known by us, are of any less universal character, than the law of gravitation. Upon each and all of these, once that they are determined, we depend with the conviction of perfect certainty. It has been thought by some that this reliance on the constancy of nature, is an instinctive feeling of the human breast, an original impulse of our nature. But be this as it may, the feeling is one, which if accompanied by a proper estimate of circumstances, is never misplaced. We may be deceived by external appearances, but this source of error apart, the uniformity and universality of the laws of nature is, so far as the range of its just application extends, the most solid foundation of human certainty to which we have yet attained.
We have seen how all the generalisations of science point to the one conclusion, that material nature through all her parts is subject to an inflexible necessity, a necessity which seems to inhere in the very idea of matter, and to be inseparable from all the conditions of its existence. Here then the question suggests itself to us: does the dominion of science terminate with the world of matter, or is there held out to us the promise of something like exact acquaintance, however less in extent, with the interior and nobler province of the mind? The inquiry is twofold, and we may consider it as involving the following questions:
First, whether there exist, with reference to our mental faculties, such general laws as are necessary to constitute a science; for we have seen that it is essentially in the recognition of general laws, not of particular facts, that science consists.
Secondly, supposing that such general laws are discoverable, what is the nature of the relation which the mind sustains towards them? Is it, like that of external nature, a relation of necessary obedience, or is it a relation of some distinct kind having no example and no parallel in the material system?9 These I conceive to be questions of a perfectly definite character, and it seems to me that they admit of an equally definite answer. First, we are to inquire if the mind is a proper object of science.
That in some sense the moral and the intellectual constitution of man are proper objects of scientific inquiry, must be conceded by all who recognise the existence either of general truths in morals, the knowledge of which may be drawn from our own consciousness, or of any fixed principles in the right operations of human reason. Neither of these can be derived from a merely external source. How varied soever the materials which are brought before the mind, there exist within, principles of thought and reason, which are of common application to them all, and are borrowed from none. There are also certain other principles which are of a more special character, yet, equally with the former, have their seat in the mind. In these principles together are involved the laws of our intellectual nature, even as in the final generalisations of physical science, we discern the laws of the material universe. If it is asked whether out of these common principles of the reason we are able to deduce the actual expressions of its fundamental laws, I reply that this is possible, and that the results constitute the true basis of mathematics. I speak here not of the mathematics of number and quantity alone, but of mathematics in its larger, and I believe, truer sense, as universal reasoning expressed in symbolical forms, and conducted by laws, which have their ultimate abode in the human mind. That such a science exists is simply a fact, and while it has one development in the particular science of number and quantity, it has another in a perfect logic. Now in this view of the laws of our intellectual nature are seen proofs of its relation to science, not less convincing than any which are written upon the physical universe. Similar evidence, though of a less formal kind, is presented in the survey of our moral constitution. Though we are conscious that we often do that which our calmer judgment condemns, not as inexpedient, but wrong; in the very fact of this condemnation we read the existence of some internal rule of right, which indeed we have power to disobey, but which we cannot ignore. To this secret testimony of the heart must be added not only the consenting force of the positive deductions of moral science which are based upon other grounds, but also the full weight of that confirmatory analogy which is drawn from the proved existence of law in our intellectual constitution. The study of Ethics thus becomes an essential part of the study of human nature. We conclude that the mind both in its intellectual and in its moral character is a proper object of science.
Secondly, we are to inquire what relation the mind sustains, to the scientific laws of its constitution.
As it is the office of the laws of reasoning to determine what is correct in the processes of thought, and of the laws of morals to determine what is right in sentiment and conduct, it may safely be inferred that whatever other relations the mind may sustain, it is constituted in some definite relation to those elements which we designate by the terms, Right and True. But in the very nature of these terms it is implied that the relation in question cannot be one of necessary or constrained obedience. Were there no liberty of error, there would be no sense of the peculiar claims and character of truth. There are then rigorous, that is, scientific laws of thought and reason, which are not necessarily obeyed. There are also, however apt to be obscured amid the importunate strivings of interest and passion, eternal rules of right, expressions of the moral character and purpose of their great Author and source. And neither do those exercise upon us any force of actual constraint. But they possess a character and a greatness of their own. They stand before us invested with attributes of reality, and of rightful supremacy, before which every opposing power seems but as a shadow or a usurpation. In these facts are presented to us the distinguishing features of our own higher nature. On its ethical side is freedom, associated with the sense of duty; on the intellectual is freedom, conjoined with the perception of the rightful demands of truth. Let the term, Freedom, be objected to, the fact, under whatever name, remains the same. The optimist may indeed inquire whether a condition of existence liable to error and irregularity, is equally perfect with one from which every such possibility is excluded. But the true idea of human progression lessens, if it does not solve the difficulty. A state of being, whose just action is maintained, and advanced by conscious effort, is felt to be better in itself than all the unintelligent obedience of nature.
I shall not here pause to dwell upon the social and economical sciences, which regard men, not as individuals, but as members of a community, and sharers of a public interest, and which are based upon the consideration of prevailing motives, rather than the requirements of an ideal standard of conduct.10 As men cannot be divested of their individuality, such sciences do not profess to attain the formal strictness of those which have been already considered. They, however, afford us valuable information as to the general tendencies of society and of institutions; and thus constitute a very important branch of knowledge. It is remarkable with what uniformity those causes operate upon large collections of men, which in the individual seem to merge and be lost amid a variety of conflicting influences. I pass over in like manner some other departments of knowledge, which, depending chiefly upon classification, may be regarded as the precursors of science, rather than science. Let us then revert to what has been said, and endeavour to recapitulate, in a few words, the conclusions which have been arrived at.
Science, then, we may regard as the joint result of the teachings of experience, and the desires and faculties of the human mind. Its inlets are the senses; its form and character are the result of comparison, of reflection, of reason, and of whatever powers we possess, whereby to perceive relations, and trace through its successive links the chain of cause and effect. The order of its progress is from particular facts to collective statements, and so on to universal laws. In Nature it exhibits to us a system of law enforcing obedience, in the Mind a system of law claiming obedience. Over the one presides Necessity; over the other, the unforced obligations of Reason and the Moral Law. Such I conceive to be the true conception of Science. It is a conception in which different elements are involved, partly appertaining to the pure and abstract nature of the object, partly to its more special relation to human conditions. Let us endeavour, from the careful review of these elements, to deduce a reply to the further inquiries,—What are the benefits which science confers? What are the claims it possesses upon our regard?
A narrow estimate of human objects is not likely to be a just one, and even in the sober view of reason, things are valuable upon very different grounds; some things for their own sake, some as means toward the attainment of an ulterior good. It might be well if the actual pursuits of mankind were more often regulated by some deliberate judgment of this nature. Custom, however, and the opinion of others too often prescribe to men what ends they shall pursue, and to what extent they shall follow them. And were it not that in such cases the pursuit often yields that enjoyment which the object sought either does not or cannot produce, we might be tempted to think that the restless strivings of humanity are even more vain than poet and inspired sage have pronounced them to be. Yet, notwithstanding that the aims of mankind are often misdirected, and their bearing upon private happiness yet oftener misunderstood, it is not to be questioned that there do exist ends which are worthy in themselves; worthy of all the expenditure of toil and time which their acquisition demands. To this regard they may be entitled, either as meeting some positive want of our nature, or as tending to some improvement of faculty or character, some essential convenience of life, or other acknowledged good. Now we have seen what is the general conception of Science, as presented in the results of previous discussion. Let us, then, consider some of the particulars involved in that conception, with reference to the question of utility, which is more immediately before us.
We have found it to be one of the characteristics of scientific knowledge, that it owes its origin in part to the desires and faculties of the human mind, and that it bears to them a certain relation of fitness and correspondency. Upon this fact, its first claim to our notice rests. The constitution of our nature is such, that whenever the pressure of the merely animal wants is removed, other and higher desires occupy their place. These are not necessarily to be regarded as modifications of the selfish principle. There is an appetency for knowledge which is not founded upon any perception of utility. Sometimes self-reliant and alone, it exists in solitary strength; sometimes gathering support from human sympathies,
quemcunque efferre laborem
Suadet, et inducit noctes vigilare serenas.11
I have already remarked how this desire of knowledge lends an impulse to those intellectual faculties, whose province it is to educe general truths, and how the actual subjection of Nature to law affords the means, on an unlimited scale, of exercising those faculties in the most appropriate manner.
Now in these facts it seems to me to be implied, that the pursuit of knowledge, and especially of that kind of knowledge which consists in the apprehension of general truths, is a designed end of human nature. Else wherefore was that desire of knowledge implanted? Or if the feeling be derived, rather than instinctive, wherefore was our nature so contrived that the desire of knowledge should, at a certain stage of advancement, never fail to present itself? Wherefore, too, those faculties which seem to have no other end than knowledge, and which, deprived of their fitting exercise, wither and decline? Wherefore, lastly, that wondrous constitution of external nature, so abounding in lessons of instruction, suitable to our capacity, addressed to our condition? With instances of mechanical adaptation in the works of the Divine Architect, we are all familiar. But to the reflective mind, there are few adaptations more manifest, there is none more complete, than that which exists between the intellectual faculties of man, and their scenes and occasions of exercise. Shall we not then confess that here also design is manifest? And shall not this manifestation of design serve in some degree as the indication of a sphere of legitimate employment, and, where not interfered with by other obligations, of a duty, the neglect of which cannot be altogether innocent?
There are certain further consequences resulting from this office of science as an exercise to our intellectual faculties, to which it may be proper to refer. It is scarcely needful to remark that every faculty we possess, and the intellectual among others, is strengthened by exercise. With respect, however, to the improvement of the individual mind by the discipline of science, it is to be remarked that it implies something more than a strengthening of faculties. It involves also the power of continued attention and the habit of application, the most difficult and most important of mental acquisitions. That the habit is usually an acquired one, is I think manifest, as well as that it belongs to the character rather than to the intellect. Furthermore, scientific studies, besides their direct influence upon the mental habits, instruct us in the right methods of the investigation of truth. For the discovery of truth is not commonly the result of random effort; it is usually, as we have seen, the reward of systematic labour, setting out from the careful examination of facts, and proceeding by definite steps of inductive and deductive reasoning to the evolution of principles. And in this process we need both the precept and the example afforded to us in those great results of accomplished science, which we owe to the patient labours of ages past. Finally, no small accession of intellectual force is due to the deliverance of the mind from that dark prejudice of chance in the physical, of fate in the moral world, to which Ignorance clings with inveterate grasp. Of all the delusions which have cast their baleful shade upon the path of human advancement, this is the most fatal. In the one of its forms it paralyses exertion; in the other it saps the foundation of trust in that righteous appointment which assigns to our actions, even in the present life, inevitable consequences of good or evil. I would appeal to all who have made any study of human motives, whether these are not true representations. Let us, however, bring them to the test of facts.
Careful inquiries assure us that there is a real connection of cause and effect between an undrained, uncleansed condition of our towns, and the prevalence of fever and a general high mortality.12 I suppose that there are few conclusions better established than this. Every now and then it receives fearful confirmation, when some epidemic disease, making head against all the resources of medical art, emerges from the dark lane or the noisome alley, and sweeps away the rich and the poor in one indiscriminate destruction. Men are, however, for the most part, so reluctant to admit the reality of that which they do not see with their eyes, that this teaching of science, and this confirmation of experience, are sometimes alike void of effect. They cannot perceive with their bodily senses the connection between impure air and disease, and they refuse to believe in invisible laws; or, if they acknowledge them in words, they do not give them any hearty assent. And so the scene of desolation is renewed from year to year.
Nor much unlike the above is the moral scene. No conclusion seems to rest upon a greater weight of cumulative evidence, than that a course of life governed by a consistent regard to the principles of rectitude, is the most favourable to public and private happiness. To carry this conviction into effect, requires that men should in some instances do that which is contrary to their personal interest as judged by common standards. It demands, therefore, that there should be on the part of the individual some trust in unseen principles, strong enough to resist the ever present importunity of appearances. The aspect of society does not, however, present, as its most common feature, this settled regard to principle and calm committal of the affairs of life to its direction. Now, I am very far from saying that such a course of conduct, where it is found, is solely the product of an enlightened understanding; but that this is an important element of the case, is beyond reasonable doubt. The man who has contemplated the subjection of all outward Nature to fixed laws, cannot, when he turns his gaze upon human society, think that its dispensations of good and evil are left to the strivings of self-interest or the scramble of accident. Still less, if he attend to the monitions of the internal witness, if he survey the ineradicable elements of his own being, the self-conscious Will, the authoritative Moral Perception, can he regard those dispensations as the sport of a blind fate, disposing of human affairs as if men were but the wreck and seaweed of a stormy shore. No! The discipline of true science, in disposing us to a belief in general laws, is favourable to a sound morality. If it exalts the consciousness of human power, it proportionally deepens the sense of human responsibility. If it releases us from those meshes of fatalism which bound the ancient Stoic, it is not that it may clothe us with an Epicurean liberty.
But it is not against the prejudices of ignorance alone that Science records her protest. There are dangers not less real in an over-curious spirit of speculation too much exercised in logical subtleties, too little conversant with realities. And against these dangers also the positive results of science constitute the best preservative. The scepticism of the ancient world left no deportment of human belief unassailed. It took its chief stand upon the conflicting nature of the impressions of the senses, but threw the dark shade of uncertainty over the most settled convictions of the mind; over men’s belief in an external world, over their consciousness of their own existence. But this form of doubt was not destined to endure. Science, in removing the contradictions of sense, and establishing the consistent uniformity of natural law, took away the main pillars of its support. The spirit, however, and the mental habits of which it was the product, still survive; but not among the votaries of science. For I cannot but regard it as the same spirit which, with whatever professions of zeal, and for whatever ends of supposed piety or obedience, strives to subvert the natural evidences of morals, and of that which is common alike to morals and to religion,—the existence of a Supreme Intelligent Cause. There is a scepticism which repudiates all belief; there is also a scepticism which seeks to escape from itself by a total abnegation of the understanding, and which in the pride of its new-found security, would recklessly destroy every internal ground of human trust and hope. I wish it to be understood that I do not seek to identify this spirit with any party, or even personally regard it as co-extensive with any party, but speak of it abstractly as a temper and habit of the mind, which is commonly, perhaps, the result of a too partial discipline.13 Now to this, as to a former development of the sceptical spirit, Science stands in implied but real antagonism. And as it before vindicated the possibility of natural knowledge, so it now lends all the weight of its analogies in support of the trustworthiness of human convictions, and the reality of some deep foundation of the moral order of things, behind the changeful contradictions of the present scene.
The claims of science with which we have hitherto been occupied, are founded upon its direct relations to human nature, and it is interesting to notice further the testimonies and indications bearing upon this view of the subject, which have been left by antiquity. In any inquiry as to what human nature is, such testimony is perfectly admissible, since in the records of the thoughts and feelings of a past world, we read but another development of those principles which are common to our nature in all periods and under all circumstances.
The instinctive thirst for knowledge, its disinterested character, its beneficial tendencies, are among the most favoured topics of ancient writers. Cicero dwelt upon them with a peculiar delight, and he has invested them with more than the common charm of his eloquence.14 Plato made them a chief ground of his speculations concerning the just man and the well-ordered state.15 Aristotle gave to them the testimony of one of the most laborious of human lives. Virgil devoted the fairest passage of his best poem to the delights of a calm and meditative life, occupied in the quest of truth.16 Lucretius drew from philosophical speculations the matter of what some have regarded as the noblest production of the Latin muse. Sophocles made Knowledge, in its aspect of power, the theme of incomparably the finest of his choral odes.17 Aeschylus made Knowledge, in its other aspect of patience and martyrdom, the nobler burden of his Prometheus.18 And there is ground for the conjecture that such influences were not unfelt by those older poets and seers with whom our own Milton felt the sympathy of a common fate, and desired to share the glory of a common renown. The early dawn, too, of philosophy, not to speak of its subsequent and higher development in the schools of Athens and Alexandria, is full of suggestive indications. Some records, scattered indeed, and dim, and fragmentary, still exist of the successive attempts which were made in Ionia, in the cities of Southern Italy, in Greece, to penetrate the mystery of the Universe, to declare what it is, and whence it came. In those speculations, vague as they are, we discern the irresistible longings of the human mind for some constructive and general scheme of truth, its inability to rest satisfied with the details of a merely empirical knowledge, its desire to escape into some less confined sphere of thought, and, if it might be, to hold “converse with absolute perfection.”19 Nor are the efforts to which such feelings gave birth to be regarded as accidental or unmeaning. They had a prospective significance in relation to the Science that was yet to appear. They were like the prelusive touches of some great master of harmony, which serve to awaken the feeling of expectancy and preparation. I affirm, and upon deliberate examination, that the peculiar order of the development of human thought which preceded the rise and growth of modern science, was not an arbitrary thing, but is in its main features susceptible of explanation. Though for any elucidation of the phenomena of nature, it is utterly worthless, upon the human faculties it throws a light of illustration which can scarcely be valued too highly (a).20
Beside the claims of science which are founded upon its immediate relations to human nature, there exist others of an implicit character, which nevertheless give to it far more evident material importance. I speak of its bearing upon the arts of civilised life.
We have seen how science testifies to the fact that the material creation is governed by fixed laws. Upon this truth rests the peculiar value of science as a minister to human wants, and a subjugator of the powers of nature to the will of man. All the operations of art and mechanism, which are but applied science, presuppose this constancy of nature. Because the vapour of water manifests certain constant properties of elasticity and capability of condensation, the steam-engine is possible. Because the laws of magnetic action are fixed, the compass is available for purposes of navigation. Because different species of glass have different dispersive actions upon the coloured rays of light, the achromatic telescope lends its aid to our vision. Because electricity freely traverses metallic wires, and in so doing manifests certain properties of attraction and repulsion, we are able to communicate with the absent by the electric telegraph. In a similar spirit of reliance upon the faithfulness of nature, the husbandman commits his seed to the ground, waiting till the genial influences of sun and shower shall mature it into a harvest. And such is the multiplied industry of man. To this it may be added, that the more that industry is under the control of science, the more does it consist in simply arranging the train of natural circumstances; the inherent and impassive forces of matter ever offering themselves as substitutes for animal toil and animal suffering. To this extension of man’s dominion over the inorganic world, there is no visible limit. The properties of matter, both mechanical and chemical, seem to be exhaustless in their variety, knowledge being the key to unlock their uses.
Accordingly, it has been thought by some that the results of science, conjoined with other agencies, open before the human race a career of indefinite progression. They anticipate a period when the physical evils which afflict our present state shall exist no longer, or exist in such measure only as is inseparable from a condition of mortality; when painful toil shall have been replaced by the appliances of mechanism; when the most prolific sources of disease, as crowded cities, undrained swamps, [and] pernicious indulgences, shall have disappeared before a more enlightened study of the conditions of health, and a truer appreciation of the ends of life; when the excessive inequalities of wealth, and the miseries which they entail, shall have yielded to a better moral or social economy; and when the effects of those casualties which prudence cannot avert, as earthquakes, tempests, [and] unfriendly seasons, shall either be reduced to a minimum of amount, or shall be so distributed as to fall with the least oppressive weight upon the community at large. They anticipate that in this happy state of things to come, relieved from the oppressive bondage of physical wants, man shall be at liberty to accomplish, and actually shall accomplish, the higher ends of his being; that while the earth shall shine with more than its pristine beauty, the human family shall not only be clothed with the fair assemblage of the moral virtues, but shall add to them that crown and safeguard of knowledge which has been won from the hard experience of ages of error and suffering.
Speculations of this kind are abused, if they only minister to the sense of human power and pride. They have their use when they instruct us, by the comparison of our actual attainments in the measures of a just and happy life, with that ideal standard to which reason and religion point. Let us ask ourselves why that better condition of things is so far from being realised. The probable conclusion will be, that the impediment is not in any invincible repugnancy in the laws of material nature, nor in any want of power and energy in the human intellect. There seems in the present day to be even a superfluous activity of invention, busying itself to accomplish ends that are not valuable, and ministering to a fantastic vanity. Here, then, we are brought again to that position around which all speculations concerning the true welfare of our species seem to revolve, viz., that it essentially contains a moral element.
But to turn this discussion to some practical issue. Whether that higher state of good shall be realised upon earth or not, they who devote themselves to the pursuits of science will not err, if they keep the prospect of it before them as the scope of their practical efforts. Though contemplation is one end of knowledge, action is another; and if the spirit of science is concentrative in its individual efforts, it is generous and diffusive in its wider aims. I speak here, however, of general tendencies. To make immediate utility the sole guide of scientific research, would defeat the object in view. Let there be a liberal union of the love of truth for its own sake, and the desire to make that truth serviceable to the world, and the chief ends for which knowledge is valuable, will be secured together.
I have now endeavoured to impart to you my own views of the nature and claims of Science. I have in doing this been careful to avoid all exaggeration, believing that the moderation and the exactness which characterise Science should be manifest in its advocacy. What I have thus sought however imperfectly to portray, is some faint image of Truth, partly in her essential lines and features, partly in her immediate aspect and relation to ourselves. And I would now ask you, if after all deductions for the imperfection of the sketch, there is not something in the object that should command our rational esteem; something that may even justify, if I may be allowed the expression, a sober enthusiasm: not that transient blaze of feeling of which, too often, the ashes alone survive, to embitter regret, when the freshness of life’s most precious years is irrecoverably gone; but that ardour of quiet and steadfast energy which addresses itself to great ends, knowing their difficulties and patiently subduing them. Such has been the feeling of all who have accomplished any eminent good, whether for their own or for a future age, of all the great masters in art and letters, in science and legislation. Such, in the more humble sphere that has been allotted to ourselves, is the feeling that we should strive to cultivate.
And if, in conclusion, I might say a few words of more special application to this country, and to present circumstances, I would remark, that though to choose or to reject the offered benefits of knowledge is a point within our own election, it is an error to suppose that the conduct of any individual or of any society in this matter can affect its final issues in the world. There may be periods in which the prospects of science, and with them those of human improvement, are sufficiently discouraging. The strong tide of party may set against it. Detraction may assail its friends, misrepresentation sully and distort its beneficent aims. Nevertheless, it is not given to such principles and to such means to accomplish any permanent triumph. Calumny shall not prevail forever. Violence and injustice shall not always usurp the place of reason. There shall be a time when men shall be judged according to their spirit and their deeds. And then shall Truth assert her rightful claims. Science shall vindicate her divine mission in the increase of the sum of human good. Obscured by the mists of prejudice, forgotten amid the strife of parties, she but the more resembles those great luminaries of heaven, which pursue their course undismayed above the rage of tempests, or amid the darkness of eclipse.
The constant effort of philosophy in her earlier stages was to establish a basis for a purely deductive system of knowledge. This, which is the final result of united experience and science, was the first aim of speculative thought, antecedent to all true science and to all exact experience. Destitute of these aids, there seems to have been but one mode in which the human mind could proceed in its quest of philosophy, viz., by projecting its own laws and conditions upon the universe, and viewing them as external realities. Such appears to me to be the true ground upon which the earlier phases of the Greek philosophy are to be explained.
The prominent idea of the earliest schools, the Ionic, the Eleatic, &c., was that the universe was a unity. They differed in their account of this unity, variously explaining it by water, air, fire, intelligence, &c.; but the existence of some fundamental unity, comprising the whole of phenomena, was, in perhaps all of them, an agreed point. The terms unity and universe, seem to have been almost regarded as convertible. The pantheistic language of Xenophanes, who, “casting up his eyes to the whole expanse of heaven, declared that the One was God,” is a type of their most prevalent cast of thought—Aristotle, Metaphysics, i. 6.
In a subsequent stage of philosophy—subsequent in the order of thought, and for the most part in that of time also—there was superadded to the above conception of unity as a ground of phenomena, that of a fundamental dualism in Nature. Existence was viewed as derived from the blending or the strife of opposing elements—good and evil, light and darkness, being and non-being, matter and form, &c. To the latest periods of speculation in the ancient world, these modes of thought, of which the Manichean doctrine was but the most eminent and most practical instance, prevailed; and in those modern schemes of philosophy, “falsely so-called,” which attempt to deduce the knowledge of Nature, a priori, from some purely metaphysical principle, the same influence is apparent. Now, so wide an agreement, even in what is false, must have some foundation in reality, and ought to be regarded as a misapplication of truth rather than as a fortuitous coincidence of errors. The foundation must be sought for in the ultimate laws of thought, and the positive conclusions of science serve to show its real nature.
All correct reasoning consists of mental processes conducted by laws which are partly dependent upon the nature of the subject of thought. Of that species of reasoning which is exemplified in Algebra, the subject is quantity, the laws are those of the elementary conceptions of quantity and of its implied operations. Of Logic, the subject, is our conceptions of classes of things, represented by general names; the ultimate laws are those of the above conceptions and of the operations connected therewith. Let these two systems of thought be placed side by side, expressed, as they admit of being, in the common symbolical language of mathematics, but each with its own interpretations—each with its own laws; and together with much that is obviously common—so much, indeed, as to have fostered the idea that Algebra is merely an application of Logic, there will be seen to exist real differences and agreements hitherto unnoticed, but not without influence on the course of human thought. The conception of the universe in the one system will occupy the place of that of unity in the other, not through any likeness of nature, as was once supposed, but through subjection to the same formal laws. Moreover, at the root of the logical system, there will be found to exist a law, founded in the nature of the conception of “class,” to which the conceptions of quantity, as such, are not subject, and which explains the origin, though it does not furnish the justification of the dualistic tendency above adverted to. I conceive it unnecessary to show, that a law of the mind may produce its effect upon thought and speculation, without its presence being perceived. Whatever, too, may be the weight of authority to the contrary, it is simply a fact that the ultimate laws of Logic—those alone upon which it is possible to construct a science of Logic—are mathematical in their form and expression, although not belonging to the mathematics of quantity.
My apology for introducing in this place observations of a somewhat technical character is, that in discussing the relations of science to human nature, it seems necessary, or at least desirable, to consider the subject in the light of past as well as of present experience; and to this end, the study of the logical or pre-inductive stage of science is important. But there is also a great collateral interest in the inquiry. The truly scientific study of the laws of thought sets in clear view the distinctive elements of our intellectual constitution—its subjection, like external Nature, to mathematical laws—the difference of the kind of subjection manifest in the two cases. It would seem that this is a fundamental difference. If we strive to conceive of our nature, in its most perfect state, the intellect assenting only to what is true, the will choosing only what is good, the consciousness that all this might, without any violation of our actual constitution, be otherwise, would appear to be a necessary adjunct to that conception. The view of this subject maintained in an earlier portion of the lecture, seems to me to be thus in strict accordance with the proved results of science.