which relates only to the past, must be an original principle of our
nature. There is a tendency in the very constitution of the mind
from which the expectation arises,--a tendency that, in every thing
which it adds to the mere facts of experience, may truly be termed
_instinctive_; for though that term is commonly supposed to imply
something peculiarly mysterious, there is no more real mystery in it
than in any of the simplest successions of thought, which are all, in
like manner, the results of natural tendency of the mind to exist in
certain states, after existing in certain other states. The belief
is, a state or feeling of the mind as easily conceivable as any other
state of it,--a new feeling, arising in certain circumstances as
uniformly as in certain other circumstances. There arise other states
or feelings of the mind, which we never consider as mysterious; those,
for example, which we term the sensations of sweetness or of sound.
To have our nerves of taste or hearing affected in a certain manner,
is not, indeed, to taste or to hear, but it is immediately afterwards
to have those particular sensations; and this merely because the mind
was originally so constituted, as to exist directly in the one state
after existing in the other. To observe, in like manner, a series
of antecedents and consequents, is not, in the very feeling of the
moment, to believe in the future similarity, but, in consequence of a
similar original tendency, it is immediately afterwards to believe,
that the _same antecedents_ will invariably be followed by the _same
consequents_. That this belief of the future is a state of mind very
different from the mere perception or memory of the past, from which
it flows, is indeed true; but what resemblance has sweetness, as a
sensation of the mind, to the solution of a few particles of sugar on
the tongue,--or the harmonies of music, to the vibration of particles
of air? All which we know, in both cases, is, that these successions
regularly take place; and in the regular successions of nature,
which could not, in one instance more than in another, have been
predicted without experience, nothing is mysterious, or every thing is
mysterious. It is wonderful, indeed,--for what is not wonderful?--that
any belief should arise as to a _future_ which as yet has no existence;
and which, therefore, cannot, in the strict sense of the word, be an
object of our knowledge. But, when we consider Who it was who formed
us, it would, in truth, have been more wonderful, if the mind had been
so differently constituted that the belief had not arisen; because, in
that case, the phenomena of nature, however regularly arranged, would
have been arranged in vain, and that Almighty Being, who, by enabling
us to foresee the physical events that are to arise, has enabled us
to provide for them, would have left the creatures, for whom he has
been so bounteously provident, to perish, ignorant and irresolute, amid
elements that seemed waiting to obey them,--and victims of confusion,
in the very midst of all the harmonies of the universe.
Mr Hume, indeed, has attempted to show, that the belief of the
similarity of future sequences of events is reducible to the influence
of custom, without the necessity of any intuitive expectation; but he
has completely failed in the reasoning with which he has endeavoured
to support this opinion. Custom may account for the mere suggestion of
one object by another, as a part of a train of images, but not for that
belief of future realities, which is a very different state of mind,
and which, perhaps, does not follow every such suggestion, however
frequent and habitual. The phenomenon A, a stone has a thousand times
fallen to the earth; the phenomenon B, a stone will always, in the same
circumstances, fall to the earth; are propositions that differ as much
as the propositions, A, a stone has _once_ fallen to the earth; B, a
stone will always fall to the earth. At whatever link of the chain we
begin, we must still meet with the same difficulty--the conversion of
the past into the future. If it be absurd to make this conversion at
one stage of inquiry, it is just as absurd to make it at any other
stage; and, as far as our memory extends, there never was a time at
which we did not make the instant conversion,--no period, however
early, at which we were capable of knowing that a stone had fallen,
and yet believed that, in exactly the same circumstances, there was
no reason to suppose that it would fall again. But on this particular
error of Mr Hume, the very narrow outline, within which the present
sketch is necessarily bounded, will not permit me to enlarge. I have
examined it, at considerable length, in the third edition of the
Inquiry which I have published on the Relation of Cause and Effect.
It is more immediately our present purpose to consider, What it truly
is which is the object of inquiry, when we examine the physical
successions of events, in whatever manner the belief of their
similarity of sequence may have arisen? Is it the mere series of
regular antecedents and consequents themselves? or, Is it any thing
more mysterious, which must be supposed to intervene and connect them
by some invisible bondage?
We see, in nature, one event followed by another. The fall of a
spark on gunpowder, for example, followed by the deflagration of the
gunpowder; and, by a peculiar tendency of our constitution, which we
must take for granted, whatever be our theory of power, we believe,
that as long as all the circumstances continue the same, the sequence
of events will continue the same; that the deflagration of gunpowder,
for example, will be the invariable consequence of the fall of a spark
on it;--in other words, we believe the gunpowder to be susceptible of
deflagration on the application of a spark,--and a spark to have the
power of deflagrating gunpowder.
There is nothing more, then, understood in the trains of events,
however regular, than the regular order of antecedents and consequents
which compose the train; and between which, if any thing else existed,
it would itself be a part of the train. All that we mean, when we
ascribe to one substance a susceptibility of being affected by another
substance, is, that a certain change will uniformly take place in it
when that other is present;--all that we mean, in like manner when we
ascribe to one substance a power of affecting another substance, is,
that, when it is present a certain change will uniformly take place
in that other substance. Power, in short, is significant not of any
thing different from the invariable antecedent itself, but of the mere
invariableness of the order of its appearance in reference to some
invariable consequent,--the invariable antecedent being denominated
a _cause_, the invariable consequent an _effect_. To say, that water
has the power of dissolving salt, and to say, that salt will always
melt when water is poured upon it, are to say precisely the same
thing;--there is nothing in the one proposition, which is not exactly,
and to the same extent, enunciated in the other.
It would, indeed, be a very different theory of causation, if, without
taking into account the important circumstance of invariableness or
the uniform certainty of being at all times followed by a particular
event, we were to say, that power is mere antecedence; for there can
be no question, that phenomena precede other phenomena, which we never
consider as having any permanent relation to them. They are regarded
as antecedents, but not invariable antecedents, and the reason of this
is obvious. Innumerable events are constantly taking place together
in the immense system of the universe. There must, therefore, always
be innumerable co-existing series, the parts of each of which, though
permanently related to each other, may have no permanent relation
to the parts of the other series; and one event of one series, may
thus precede, not its own effect merely, which is to be its constant
and uniform attendant, in all similar circumstances, but the events
also of other co-existing series, which may never occur with it again
at the same moment. There is no superstition in believing that an
eclipse _may_ be followed by a pestilence, or an unpleasant dream
by some unforeseen calamity of the day, though there would be much
superstition in believing, that these antecedents and consequents
had any _permanent_ relation to each other. In ordinary and familiar
cases, at least, every one knows sufficiently the distinction of
what is thus _casual_ only, and what is _invariable_ in the order of
nature. Yet it is only by losing all sight of a distinction so very
obvious, and confounding invariable with casual consequences, that
Dr Reid, and other eminent philosophers, have been led into much
laborious argumentation, in the confidence of confuting one of the
simplest and justest of metaphysical opinions. To prove that power
is more than invariable antecedence, they prove that it is more than
casual antecedence, and that events do not follow each other, loosely
and confusedly, as if antecedents could be invariable, which had not
consequents as invariable, or, as if an uniform series were not merely
another name for a number of uniform antecedents and consequents. A
_cause_ is, perhaps, not that which has merely _once_ preceded an
event; but we give the name to that which _has_ always been followed
by a certain event, _is_ followed by a certain event, and according to
our belief, _will continue_ to be in future followed by that event, as
its immediate consequent; and causation, power, or any other synonymous
words which we may use, express nothing more than this permanent
relation of that which has preceded to that which has followed. If this
invariableness of succession, past, present, and future, be not that
which constitutes one event the _effect_ of another, Dr Reid, at least,
has not pointed out any additional circumstance which we must combine
with it, in our definition of an effect, though he has shown, indeed,
with most abundant evidence, if any evidence at all were necessary,
that the antecedents and consequents are not the same; that we use
active and passive verbs, in different senses, applying, as might well
be supposed, the one to the antecedent, the other to the consequent;
that we speak of effects and causes as if truly different, since it
is unquestionably not the same thing to _follow_ uniformly a certain
change, and to _precede_ uniformly a certain change, and that we never
think of giving those names where we do not conceive that there is some
permanent relation. But, though these distinctions might be allowed
to have irresistible weight, in opposition to the scepticism, if such
extravagant scepticism there ever were, which affirmed the sequences
of events to be altogether casual and irregular, they are surely of
no weight against that simple definition of power, which affirms it
to consist in the probability of the invariable _sequence_. of some
event as its immediate _consequent_; since this very regularity of the
sequences, which is supposed by the definition, must, of itself, have
given occasion to all those distinctions of thought and language which
Dr Reid has adduced.
That one event should invariably be followed by another event,
is indeed, it will be allowed, as every thing in nature is, most
wonderful, and can be ascribed only to the infinite source of every
thing wonderful and sublime; the will of that divine Being, who gave
the universe its laws, and who formed these with a most beneficent
arrangement for the happiness of his creatures, who, without a belief
in the uniformity of these laws, to direct their conduct, could not
have known how to preserve even their animal existence. But the
uniformity of succession is surely not rendered less wonderful, by a
mere change of name. It is the same unaltered wonder still, when we
ascribe the term _power_ to the prior of two events, as when we ascribe
to it the exactly synonymous phrase _invariableness of antecedence_;
each of these terms implying nothing more than that the one event
cannot take place without being immediately followed by the other.
The permanence and uniformity of the relation are the essential
circumstances. To be that which cannot exist, without being instantly
followed by a certain event, is to be the _cause_ of the _event_, as
a correlative _effect_. It is impossible for us to believe, that the
invariable antecedent is any thing but the cause, or the cause any
thing but the invariable antecedent; as it is impossible for us to
believe that _homo_ is the Latin synonime of _man_, and yet that _man_
is not the English synonime of _homo_.
To know the _powers_ of nature, is, then, nothing more than to know
what antecedents are and will be _invariable_, followed by what
consequents; for this invariableness, and not any distinct existence,
is all which the shorter term power, in any case, expresses; and this,
and this alone, is the true object of physical inquiry, in that second
point of view, in which we have considered it, as directed to the
successions of events.
Whenever, therefore, the question is put, as to any object, What is
it? there are two answers, and only two answers, that can be given
with meaning. We may regard it as it exists _in space_, and state the
elements that co-exist in it, or rather that constitute it; or we may
regard it, as it exists _in time_, and state, in all the series of
changes, of which it forms an invariable part, the objects to which it
is related as antecedent or consequent.
To combine these two views of nature, as it exists in space and time,
and to know, with perfect accuracy, every element of every aggregate,
and every series of changes, of which each forms, or can form, a
part, would be to know every thing which can be physically known of
the universe. To extend our mere physical inquiry still farther into
the phenomena of nature, after this perfect knowledge, would be to
suppose erroneously, that, in the compounds before us, of which we
know every element, there is some element, not yet discovered, or, in
the well-known successions of events, some antecedent or consequent
as yet unobserved; or it would be to inquire without any real object
of inquiry,--a sort of investigation, which, for two thousand years,
was almost the sole employment of the subtile and the studious, and
which is far from having perished, with those venerable follies of
the schools, at which we know so well how to smile, even while we are
imitating them, perhaps, with similar errors of our own. I cannot
but think, for example, that, on this very subject of the connexion
of events, the prevalent notions and doctrines, even of very eminent
philosophers, are not far advanced beyond the verbal complexity of the
four causes of which Aristotle treats, the _material_, the _formal_,
the _efficient_, and the _final_; or Plato's five causes, which Seneca,
in one of his Epistles, briefly defines the _id ex quo_, the _id a
quo_, the _id quo_, the _id ad quod_, and the _id propter quod_,[26]
and though there were no other evidence than this one subject affords,
it would still, I fear, prove sufficiently, that, with all our
manifest improvements in our plans of philosophical investigation, and
all the splendid discoveries to which these improvements have led,
we have not wholly lost that great art, which, for so long a time,
supplied the place of the whole art of philosophizing--the art of
inquiring assiduously, without knowing what we are inquiring about.
It is an art, indeed, which, there is too much reason to suppose,
will accompany philosophy, though always, it is to be hoped, in less
and less proportion, during the whole course of its progress. There
will forever be points, on which those will reason ill, who may yet
reason, with perfect accuracy, on other matters. With all those sublime
discoveries of modern times, which do us so much honour, and with
that improved art of discovery, which is still more valuable to us
than the discoveries produced by it, we must not flatter ourselves
with exemption from the errors of darker ages--of ages truly worthy
of the name of dark, but to which we perhaps give the name, with more
readiness, because it seems to imply, that our own is an age of light.
Our real comfort, in comparing ourselves with the irrefragable and
subtile doctors of other times, is not that we do not sometimes reason
as indefatigably ill as they, and without knowing what we are truly
reasoning about, but that we do this much _less_ frequently, and are
continually lessening the number of cases, in which we reason as ill,
and increasing, in proportion, the number of cases, in which we reason
better, and do truly know, what objects we are seeking.
Of all the cases, however, in which it is of importance, that the
mind should have precise notions of its objects of inquiry, the most
important are those which relate to the subject at present considered
by us; because the nature of power, in the relation which it is
impossible for us not to feel of events, as reciprocally effects and
causes, must enter, in a great measure, into every inquiry which we are
capable of making, as to the successive phenomena, either of matter
or of mind. It is of so much importance, therefore, to our future
inquiries, that you should know what this universal and paramount
relation is, that I have dwelt on it at a length, which I fear must
have already exhausted your patience; since it is a discussion, I
must confess, which requires considerable effort of attention; and
which has nothing, I must also confess, to recommend it, but its dry
utility. I trust, however, that you are too well acquainted with the
nature of science, not to know, that it is its utility which is its
primary recommendation; and that you are too desirous of advancing in
it, not to disregard the occasional ruggedness of a road, which is far
from being always rugged. It may be allowed to him, who walks only for
the pleasure of the moment, to turn away from every path, in which he
has not flowers and verdure beneath his feet, and beauty wherever he
looks around. But what should we have thought of the competitor of
the Olympic course, whose object was the glory of a prize, contested
by the proudest of his contemporary heroes, if, with that illustrious
reward before him,--with strength and agility that might ensure him
the possession of it,--and with all the assembled multitudes of Greece
to witness his triumph, he had turned away, from the contest, and the
victory, because he was not to tread on softness, and to be refreshed
with fragrance, as he moved along! In that knowledge which awaits your
studies, in the various sciences to which your attention may be turned,
you have a much nobler prize before you; and, therefore, I shall not
hesitate to call forth occasionally all the vigour of your attention,
at the risk of a little temporary fatigue, as often as it shall appear
to me, that, by exciting you to more than ordinary intellectual
activity, I can facilitate your acquisition of a reward, which the
listless exertions of the indolent never can obtain, and which is as
truly the prize of strenuous effort, as the Palms of the Circus or the
Course.
FOOTNOTES:
[25] Essay concerning Human Understanding, book iv. c. 3. sec. 25, 26.
[26] Epist. 65.
LECTURE VII.
ON POWER, CAUSE, AND EFFECT.
My last Lecture, Gentlemen, was chiefly employed in examining _what
it is_, which is the real object of inquiry, when we consider the
phenomena of nature as successive; and we found, that, by an original
principle of our constitution, we are led, from the mere observation
of change, to believe, that, when similar circumstances recur, the
changes, which we observed, will also recur in the same order,--that
there is hence conceived by us to be a permanent relation of one
event, as invariably antecedent, to another event, as invariably
consequent,--and that this _permanent relation_ is all which
constitutes _power_. It is a word, indeed, of much seeming mystery; but
all which is supposed to be mysterious and perplexing in it vanishes,
when it is regarded in its true light as only a short general term,
expressive of invariable antecedence, or, in other words, of that,
which cannot exist in certain circumstances, without being immediately
followed by a certain definite event, which we denominate an effect, in
reference to the antecedent, which we denominate a cause. To express,
shortly, what appears to me to be the only intelligible meaning of
the three most important words in physics, immediate invariable
_antecedence_, is _power_,--the immediate invariable _antecedent_, in
any sequence, is a _cause_,--the immediate invariable _consequent_ is
the correlative _effect_.
The object of philosophic inquiry, then, in that second department
of it, which we considered with respect to the phenomena of nature
as successive, we have found not to be any thing different from the
phenomena themselves, but to be those very phenomena, as preceding
or following, in certain regular series. Power is not any thing that
can exist separately from a substance, but is merely the substance
itself, considered in relation to another substance,--in the same
manner, as what we denominate _form_, is not any thing separate from
the elementary atoms of a mass, but is merely the relation of a number
of atoms, as co-existing in apparent contact. The sculptor at every
stroke of his chisel, alters the form of the block of marble on which
he works, not by communicating to it any new qualities, but merely by
separating from it a number of the corpuscles, which were formerly
included by us, in our conception of the continuous whole; and when
he has given the last delicate touches that finish the Jupiter, or
the Venus, or Apollo, the divine form which we admire, as if it had
assumed a new existence beneath the artist's hand, is still in itself
_unaltered_,--the same quiescent mass, that slumbered for ages in the
quarry of which it was a part.
Quale fuscæ marmor in Africæ
Solo recisum, sumere idoneum
Quoscunque vultus, seu Diana
Seu Cytheræa magis placebit;
Informis, ater, sub pedibus jacet,
Donec politus Phidiaca manu
Formosa tandem destinatæ
Induitur lapis ora divæ.
Jam, jamque poni duritiem placens,
Et nunc ocelli, et gratia mollium
Spirat genarum, nunc labella et
Per nivium coma sparsa collum.
The _form_ of bodies is the relation of their elements to each other
_in space_,--the _power_ of bodies is their relation to each other
_in time_; and both form and power, if considered separately from
the number of elementary corpuscles, and from the changes that arise
successively, are equally abstractions of the mind, and nothing
more. In a former Lecture, I alluded to the influence of errors with
respect to the nature of abstraction, as one of the principal causes
that retard the progress of philosophy. We give a name to some common
quality of many substances; and we then suppose, that there is in
it something real, because we have given it a name, and strive to
discover, what that is in itself, which, in itself, has no existence.
The example, which I used at that time, was the very striking one, of
the _genera_, and _species_, and the whole classes of ascending and
descending universals of the schools. I might have found an example,
as striking, in those abstractions of form and power, which we are
now considering,--abstractions, that have exercised an influence
on philosophy, as injurious as the whole series of universals in
Porphyry's memorable tree, and one of which, at least, still continues
to exercise the same injurious influence, when the tree of Porphyry has
been long disregarded, and almost forgotten.
In the philosophy of Aristotle, _form_, which all now readily allow
to be a mere abstraction of the mind, when considered separately from
the figured substance, was regarded as something equally real with
matter itself; and indeed, _matter_, which was supposed to derive from
_form_ all its qualities, was rather the less important of the two. Of
substantial forms, however, long so omnipotent, we now hear, only in
those works which record the errors of other ages, as a part of the
history of the fallible being, man, or in those higher works of playful
ridicule, which convert our very follies into a source of amusement,
and find abundant materials, therefore, in what was once the wisdom of
the past. Crambé, the young companion of Martinus Scribblerus, we are
told, “regretted extremely, that substantial forms, a race of harmless
beings, which had lasted for many years, and afforded a comfortable
subsistence to many poor philosophers, should be now hunted down like
so many wolves, without the possibility of a retreat. He considered
that it had gone much harder with them, than with _essences_, which
had retired from the schools, into the apothecaries' shops, where
some of them had been advanced into the degree of quintessences. He
thought there should be a retreat for poor substantial forms among
the Gentlemen Ushers at Court, and that there were indeed substantial
forms, such as _forms of Prayer_ and _forms of Government_, without
which the things themselves could never long subsist.”[27]
The subject of this pleasantry is, indeed, it must be owned, so
absurd in itself, as scarcely to require the aid of wit, to render it
ridiculous; and yet this more than poetic personification of the mere
figure of a body, as itself a separate unity, which appears to us too
absurd almost to be feigned as an object of philosophic belief, even
to such a mind as that of Crambé, was what, for age after age, seemed
to the most intelligent philosophers a complete explanation of all the
wonders of the universe; and _substantial forms_, far from needing a
retreat among Gentlemen Ushers at Court, had their place of highest
honours amid Doctors and Disputants, in every School and College,
where, though they certainly could not give science, they at least
served the temporary purpose of rendering the want of it unfelt, and of
giving all the dignity which science itself could have bestowed.