seldom fails to bring before us our common and equal nature. In spite
of all the little distinctions which a churchyard exhibits, in mimic
imitation, and almost in mockery, of the great distinctions of life,
the turf, the stone with its petty sculptures, and all the columns and
images of the marble monument; as we read the inscription, or walk over
the sod, we think only _of what lies beneath in undistinguishable
equality_. There is scarcely any one on whom these two great equalizing
objects, sickness and the sight of death, have not produced, for a
short time, at least, some salutary moral impression. But these are
objects which cannot often occur, and which are accompanied with too
many distressing circumstances, to render it desirable that they should
be of very frequent occurrence. The study of the _mind_, of our common
moral and intellectual nature, and of those common hopes which await
us, as immortal beings, seems in some degree to afford the advantage,
without the mixture of evil: for, though in such speculative inquiries,
the impression may be less striking than when accompanied with painful
circumstances, it is more permanent, because, from the absence of those
powerful circumstances, it is more frequently and willingly renewed.
In the philosophy of mind, all those heraldic differences which have
converted mere human vanity into a science, are as nothing. It is _man_
that is the object of investigation, and man with no distinctions that
are adventitious. The feelings, the faculties, which we consider, are
endowments of the rich and powerful indeed; but they are endowments
also of the meanest of those on whom they look with disdain. It is
something, then, for those whose thoughts are continually directed
by external circumstances, to that perilous elevation on which they
are placed, to be led occasionally, as in such inquiries they must
be, to measure themselves and others without regard to the accidental
differences of the heights on which they stand, and to see what it
is in which they truly _differ_, and what it is in which they truly
_agree_.
In the remarks already made, on the study of the Science of Mind, we
have considered its effects on the progress of the other sciences,
and on the moral dispositions. But, though the study had no effects
of this kind, moral or intellectual, is not the mind itself a part of
nature, and _as a mere physical object_, deserving of our profoundest
and most intent investigation? or shall it be said, that while we
strive, not merely to measure the whole earth, and to follow in our
thought the revolutions of these great orbs, whose majesty may almost
be said to force from us this homage of admiration, but to arrange,
in distinct tribes, those animalcular atoms, whose very existence we
learn only from the glass through which we view them; the observing
and calculating mind itself is less an object of universal science,
than the antennae of an insect, or the filaments of a weed? Would it
be no reproach to man, even though he knew all things besides, that
he yet knew far less accurately than he might know, his own internal
nature,--like voyagers who delight in visiting every coast of the most
distant country, without the slightest acquaintance, perhaps, with the
interior of their own?
Qui terræ pelagique vias, mundique per omnes
Articulos spatiatur ovans, metasque suorum
Herculeas audet supra posuisse laborum,
Neglectus jacet usque sibi, dumque omnia quærit,
Ipse sui quæsitor abest; incognita tellus
Solus nauta latet, propiorque ignotior orbis.
Would the lines which follow these, if indeed there were any one to
whom they were applicable in their full extent, convey praise less high
than that which might be given to the observer of some small nerve or
membrane, that had never been observed before, or the discoverer of a
new species of earth, in some pebble before unanalyzed?
Tu melior Tiphys, spreto jam Phasidis auro,
In te vela paras, animatos detegis orbes,
Humanasque aperis ausis ingentibus oras.
Jamque novos laxari sinus, animæque latentis
Arcanas reserare vias, cœlosque recessus
Fas aperire tibi, totamque secludere mentem.
To the _mind_, considered as a mere object of physical inquiry, there
is one circumstance of interest, that is peculiar. It is the part of
our mixed nature which we have especially in view as often as we think
of _self_,--that by which we began to exist, and continue to exist, by
which in every moment of our being, we have rejoiced, and hoped, and
feared, and loved; or rather, it is that which has been itself, in all
our emotions, the rejoicer, the hoper, the fearer. To inquire into the
history of the mind, therefore, is in truth to look back, as far as it
is permitted to us to look back, on the whole history of our life. It
is to think of those many pleasing emotions which delighted us when
present, or of those sadder feelings, which when considered as past,
become delightful, almost like the feelings that were in themselves
originally pleasing, and in many cases, are reviewed with still greater
interest. We cannot attempt to think of the origin of our knowledge,
without bringing before us scenes and persons most tenderly familiar;
and though the effect of such remembrances is perhaps less powerful,
when the mind is prepared for philosophical investigation, than in
moments in which it is more passive, still the influence is not
wholly lost. He must be a very cold philosopher indeed, who, even in
intellectual analysis, can retrace the early impressions of his youth,
with as little interest as that with which he looks back on the common
occurrences of the past day.
But it is not any slight interest which it may receive from such
peculiar remembrances, that can be said to give value to the philosophy
of mind. It furnishes, in itself, the sublimest of all speculations,
because it is the philosophy of the sublimest of all created things.
“There is but one object,” says St. Augustine, “greater than the soul,
and that one is its Creator.” “Nihil est potentius illa creatura quæ
mens dicitur rationalis, nihil est sublimius. _Quicquid supra illam
est jam Creator est._” When we consider the powers of his mind, even
without reference to the wonders which he has produced on earth, what
room does man afford for astonishment and admiration! His senses,
his memory, his reason, the past, the present, the future, the whole
universe, and, if the universe have any limits, even more than the
whole universe, comprised in a single thought; and, amid all these
changes of feelings that succeed each other, in rapid and endless
variety, a permanent and unchangeable duration, compared with which,
the duration of external things is but the existence of a moment.
“O what a patrimony this! a being
Of such inherent strength and majesty,
Not worlds possest can raise it; worlds destroy'd
Not injure;[19] which holds on its glorious course,
When thine, O Nature, ends!”[20]
Such, in dignity and grandeur, is the mind considered, even
abstractedly. But when, instead of considering the mind itself, we
look to the wonders which it has performed--the cities, the cultivated
plains, and all the varieties of that splendid scene to which the art
of man has transformed the deserts, and forests, and rocks of original
nature; when we behold him, not limiting the operations of his art
to that earth to which he seemed confined, but bursting through the
very elements, that appeared to encircle him as an insurmountable
barrier--traversing the waves--struggling with the winds, and making
their very opposition subservient to his course; when we look to
the still greater transformations which he has wrought in the
_moral scene_, and compare with the miseries of barbarous life, the
tranquillity and security of a well ordered state; when we see, under
the influence of legislative wisdom, insurmountable multitudes obeying,
in opposition to their strongest passions, the restraints of a power
which they scarcely perceive, and the crimes of a single individual
marked and punished, at the distance of half the earth; is it possible
for us to observe all these wonders, and yet not to feel some curiosity
to examine the faculties by which they have been wrought, some interest
in a being so noble, that leads us to speculate on the future wonders
which he may yet perform, and on the final destiny which awaits him?
This interest we should feel, though no common tie connected us with
the object of our admiration; and we cannot surely admit that the
object of our admiration is less interesting to us, or less sublime in
nature, because the faculties which we admire are those which ourselves
possess, and the wonders such as we are capable of achieving and
surpassing.
FOOTNOTES:
[14] Seneca, Ep. 108.
[15] Dissertat. ab Arrian, collect, lib. i. c. 6.--p. 35. Edit. Upton.
[16] Seneca de otio Sapent. c. 32.
[17] Pope's Essay on Man, Ep. ii. v. 237-240, and 245-248.
[18] Lect. III.
[19] Can't injure. _Orig._
[20] Young's Night Thoughts, VI. v. 535-539.
LECTURE V.
ON THE NATURE OF PHYSICAL INQUIRY IN GENERAL.
The preceding Lectures, Gentlemen, have, I trust, sufficiently
convinced you of the _importance_ of the science on which we are to
enter,--if, indeed, many of the advantages which we have considered
were not of themselves so obvious, as readily to have occurred to your
own reflection, or at least to require less illustration, than,--in
my desire to interest not your attention merely, but your zealous
ardour, in a science which appears to me so truly to deserve it,--I
have thought necessary to give them. We have seen, how interesting the
mind is, as an object of study, _from its own intrinsic excellence_,
even though it were to be considered in no other light, than as a
mere part of the universal system of things, necessary, therefore,
to be comprehended with every other existing substance, _in a system
of general physics_. We have seen, likewise, in how many important
respects, the study of the science of Mind is favourable to the growth
of virtuous sentiment, and to the refinement and happiness of society;
and, above all, how essential an acquaintance with it is, to the proper
conduct of our inquiries,--not merely in those sciences, the objects of
which are kindred or analogous, but in every other science, the various
objects of which, however independent, and even remote from it they may
seem, must always be considered, not as they exist in _themselves_, but
as they exist in _relation to it_; since they can be known to us only
through the medium of the mental affections, or feelings, excited by
them, which have laws peculiar to themselves, and analyzed and arranged
only by our mental faculties, which have their own peculiar limits of
extent and power.
The first great division of our course of inquiry is purely
physiological. It has for its object the mind, considered as
susceptible of various states or affections, and constituting, as
it is thus variously affected, the whole phenomena of thought and
feeling, which, though expressed by a variety of terms, of functions,
or faculties, are still but the _one_ mind itself existing in different
states. On retracing these states, which form the whole progress of
our sentient, intellectual, and moral life, we have to inquire into
the properties of the substance, mind, according to the same laws of
investigation, by which we inquire into the properties of external
substances,--not by assuming principles, from which the phenomena may
be supposed to flow, but by observing and generalizing, till we arrive
at those few simple principles or laws, which, however pompous the
term _laws_ may seem, as if it denoted something different from the
phenomena themselves, and paramount to them, are in truth, nothing
more than the expression of the most general circumstances, in which
the phenomena themselves have been felt by us to agree. As we say of
gold, that it is that which is of a certain specific weight, yellow,
ductile, fusible at a certain temperature, and capable of certain
combinations,--because all these properties have been observed by
ourselves or others,--so we say of the _mind_, that it is that which
perceives, remembers, compares, and is susceptible of various emotions
or other feelings; because of all these we have been conscious, or have
observed them indirectly in others. We are not entitled to state with
confidence any quality, as a property of gold, which we do not remember
to have observed ourselves, or to have received on the faith of the
observation of others, whose authority we have reason to consider as
indubitable; and as little are we entitled to assert any quality, or
general susceptibility, as belonging to the human _mind_, of which we
have not been conscious ourselves in the feelings resulting from it, or
for which we have not the authority of the indubitable consciousness of
others. The exact coincidence, in this respect, of the physics of mind
and of matter, it is important that you should have constantly before
you, that you may not be led to regard the comparative indistinctness
and vagueness of the mental phenomena as a warrant for greater
boldness of assertion, and looseness of reasoning with respect to
them. There is, on the contrary, in such a case, still greater reason
to adhere rigidly to the strict rules of philosophizing; because the
less definite the phenomena are, the greater danger is there of being
misled in discriminating and classing them. The laws of inquiry,
those general principles of the logic of physics, which regulate our
search of truth in all things, external and internal, do not vary with
the name of a science, or its objects or instruments. They are not
laws of _one_ science, but of _every_ science, whether the objects of
it be mental or material, clear or obscure, definite or indefinite;
and they are thus universal, because, in truth, though applicable
to _many sciences_, they are only laws of _the one inquiring mind_,
founded on the weakness of its powers of discernment, in relation to
the complicated phenomena on which those powers are exercised. The
sort of reasoning which would be false in chemistry, would be false
in astronomy, would be false in the physiology of our corporeal or
intellectual and moral nature, and in all, for the same reason; because
the mind is the inquirer in all alike, and is limited, by the very
constitution of its faculties, to a certain order of inquiry, which it
must, in this case of supposed erroneous reasoning, have transgressed.
On these general laws of inquiry, as relating alike to the
investigation of the properties of _matter_ and of _mind_, it is my
intention to dwell, for some time, with full discussion; for, though
the subject may be less pleasing, and may require more severe and
unremitting attention on your part, than the greater number of the
inquiries which await us, it is still more important than any of these,
because it is, in truth, _essential_ to them all. The season of your
life is not that which gathers the harvest; it is that which prepares
the soil, by diligent cultivation, for the fruits which are to adorn
and enrich it;--or, to speak without a metaphor, you do not come here,
that you may make yourselves acquainted, in a few months, with all the
phenomena of the universe,--as if it were only to look on the motions
of the planets in an orrery, or to learn a few names of substances and
qualities,--but that you may acquire those _philosophical principles_,
which in the course of a long and honourable life, are to enable you
to render yourselves more familiar every day with the works of nature,
and with the sublime plans of its beneficent Author:--and if without
the knowledge of a single word of fact, in matter or in mind, it were
possible for you to carry away from these walls a clear notion of the
objects of inquiry, and of the plan on which alone investigation can
be pursued with advantage, I should conceive, that you had profited
far more, than if, with confused notions of the objects and plan of
investigation, you carried with you the power of talking fluently,
of observations, and experiments, and hypotheses, and systems, and of
using, in their proper places, all the hardest words of science.
I must remark, however, that I should not have thought it necessary,
thus to direct so much of your attention to the principles of
scientific inquiry in general, if I could have taken for granted,
that you had already enjoyed the benefit of the instruction of my
illustrious colleague in another Chair, whose Lectures on Natural
Philosophy, exemplifying that soundness of inquiry, which I can only
recommend, would, in that case, have enlightened you more, as to the
principles of physical investigation, than any mere rules, of which it
is possible to point out to you the utility and the excellence.
All physical science, whatever may be the variety of objects, mental or
material, to which it is directed, is nothing more than the comparison
of phenomena, and the discovery of their agreement or disagreement,
or order of succession. It is on _observation_, therefore, or on
consciousness, which is only another name for _internal_ observation,
that the whole of science is founded; because there can be no
comparison, without observation of the phenomena compared, and no
discovery of agreement or disagreement, without comparison. So far,
then, as man has observed the phenomena of matter or of mind, so far,
and no farther, may he infer, with confidence, the properties of
matter and of mind; or, in the words of the great primary aphorism of
Lord Bacon, which has been so often quoted, and so often quoted in
vain, “Homo, naturæ minister et interpres, tantum facit et intelligit,
quantum de naturæ ordine re vel mente observaverit; nec amplius scit
aut potest.”[21]
What is it that we truly mean, however, when we say, that we are
about to inquire into the nature and properties of any substance? The
question is a most important one, and is far from being so simple as
it may at first appear. From the mere misunderstanding of the import
of this question, the brightest talents of a long succession of
ages,--talents, which, with clearer views of _this single point_, might
have anticipated all the discoveries of our own time, and introduced
us, perhaps, to discoveries still more brilliant and astonishing, were
wasted in inquiries as barren as the frivolous glory which attended
them,--that produced indeed much contention, and more pride, but
produced nothing more; and, without giving any additional knowledge,
took away from ignorance only its humility, and its power of being
instructed.
What is it that we truly have in view, or should have in view, when we
inquire into the nature of a substance?
The material universe, and all the separate substances which compose
it, may be considered in _two_ lights,--either simply, as composed
of parts that co-exist, and are to our feelings continuous, so as to
form, of many separate and independent elements, one apparent whole;
or of parts that change their relative positions, constituting, by
this change of place, all the physical events of the material system
of the world; and inquiry may have reference to a substance in both,
or either of those points of view. What is this body? may be inquired
of us, when any particular body is pointed out; and the answer which
we give will be very different according to the _particular_ light in
which we may have viewed it, though it must always relate to it in
_one_ or _other_ of these two aspects. Let us suppose, for example, the
body, concerning which the question is put, to be a piece of glass;
I select intentionally a substance which is familiar to you all, and
of which many of you probably have sufficient chemical knowledge to
be acquainted with the composition. It may be asked of us, then, What
is the substance termed _glass_? and our answer will vary, as I have
said, with the view which we take of it. If we consider it merely as
a _continuous whole_, our answer will be, that it is a _compound of
alkaline and siliceous matter_--meaning that particles of alkali and
flint co-exist, and are apparently continuous, in that mass of which we
speak.
Such is _one_ of the answers which may be given to the question;
and this sort of answer is one which is very commonly given to such
questions. It is, you will perceive, nothing more than the enumeration
of the constituent parts of the substance, and considers the substance,
simply as it exists alone, without regard to any other bodies that may
exist around it, or near it, and without any allusion to change of _any
kind_.
This sort of view, however, may be altogether reversed; and, instead
of thinking of the parts that exist together in the substance, without
reference to any changes, of which it is either the agent or the
subject, we may think only of such changes, without reference to its
constituent parts.
In this latter point of view, we may say, in answer to the question, as
to the nature of the substance termed glass, that it is a transparent
substance, which, according to the general laws of refraction, bends
the light that passes through it variously, according to the different
density of the medium through which the rays have immediately passed
before arriving at it, or of the medium, through which they are to
pass after penetrating it; that it is a substance fusible at a certain
temperature, not dissolved by the common powerful acids, but soluble
in a particular acid termed the _fluoric_ acid; that, when strongly
rubbed, by certain other substances, it communicates, for a time, to
various bodies, the power of attracting or repelling other bodies; and
we may add to our description, in like manner, as many other qualities
as there are various substances which produce in it any change, or
are in any way changed by it. In all answers of this kind, you will
perceive that regard is uniformly had, not to the _mere substance_,
concerning which the question is put, but also to some other substance
with which, in consequence of some motion of one or other of the
bodies, at the time of the phenomenon of which we speak, it has changed
its relative position; for, if all the objects in nature remained
constantly at rest, it is very evident that we could have no notion of
any property of matter whatever. In the enumeration of the qualities of
glass, for example, when we speak of its properties, we suppose it to
have changed, in every case, some relative position with the _light_
that passes through it, the _heat_ that melts it, the _fluoric acid_
that dissolves it, and the various bodies that excite in it, or conduct
from it, electricity; and all these bodies, therefore, we must have in
view, in our enumeration, as much as the glass itself.
As there are only these two different aspects in which matter can
be viewed, all physical inquiry, with respect to matter, _must_, as
I have said, have reference to one of them; and if we think that we
are inquiring further concerning it, our inquiry is truly without an
object, and we know not what we seek. We may consider it, simply as it
exists in space, or as it exists in time. Any substance, considered
as it exists in space, is the mere name which ourselves give to
the co-existence of a multitude of bodies, similar in nature, or
dissimilar, in apparent continuity; considered as it exists in time,
it is that which is affected by the prior changes of other bodies,
or which itself produces a change of some sort in other bodies. As
it exists in space, therefore, we inquire into its composition, or,
in other words, endeavour to discover what are the elementary bodies
that co-exist in the space which it occupies, and that are all which
we truly consider, when we think that we are considering the compound
as one distinct body. As it exists in time, we inquire into its
susceptibilities or its powers, or, in other words, endeavour to trace
all the series of prior and subsequent changes, of which its presence
forms an intermediate link.