OF THE IDEA OF NECESSARY CONNEXION.
Having thus explained the manner _in which we reason beyond our
immediate impressions, and conclude that such particular causes must
have such particular effects_; we must now return upon our footsteps
to examine that question[12] which first occurred to us, and which we
dropped in our way, viz. _What is our idea of necessity, when we say
that two objects are necessarily connected together_? Upon this head
I repeat, what I have often had occasion to observe, that as we have
no idea that is not derived from an impression, we must find some
impression that gives rise to this idea of necessity, if we assert
we have really such an idea. In order to this, I consider in what
objects necessity is commonly supposed to lie; and, finding that it is
always ascribed to causes and effects, I turn my eye to two objects
supposed to be placed in that relation, and examine them in all the
situations of which they are susceptible. I immediately perceive that
they are _contiguous_ in time and place, and that the object we call
cause _precedes_ the other we call effect. In no one instance can I go
any farther, nor is it possible for me to discover any third relation
betwixt these objects. I therefore enlarge my view to comprehend
several instances, where I find like objects always existing in like
relations of contiguity and succession. At first sight this seems to
serve but little to my purpose. The reflection on several instances
only repeats the same objects; and therefore can never give rise to a
new idea. But upon farther inquiry I find, that the repetition is not
in every particular the same, but produces a new impression, and by
that means the idea which I at present examine. For after a frequent
repetition I find, that upon the appearance of one of the objects, the
mind is _determined_ by custom to consider its usual attendant, and to
consider it in a stronger light upon account of its relation to the
first object. 'Tis this impression, then, or _determination_, which
affords me the idea of necessity.
I doubt not but these consequences will at first sight be received
without difficulty, as being evident deductions from principles which
we have already established, and which we have often employed in our
reasonings. This evidence, both in the first principles and in the
deductions, may seduce us unwarily into the conclusion, and make us
imagine it contains nothing extraordinary, nor worthy of our curiosity.
But though such an inadvertence may facilitate the reception of this
reasoning, 'twill make it be the more easily forgot; for which reason
I think it proper to give warning, that I have just now examined one
of the most sublime questions in philosophy, viz. _that concerning the
power and efficacy of causes_, where all the sciences seem so much
interested. Such a warning will naturally rouse up the attention of
the reader, and make him desire a more full account of my doctrine,
as well as of the arguments on which it is founded. This request is
so reasonable, that I cannot refuse complying with it; especially as
I am hopeful that these principles, the more they are examined, will
acquire the more force and evidence.
There is no question which, on account of its importance, as well as
difficulty, has caused more disputes both among ancient and modern
philosophers, than this concerning the efficacy of causes, or that
quality which makes them be followed by their effects. But before they
entered upon these disputes, methinks it would not have been improper
to have examined what idea we have of that efficacy, which is the
subject of the controversy. This is what I find principally wanting in
their reasonings, and what I shall here endeavour to supply.
I begin with observing, that the terms of _efficacy, agency, power,
force, energy, necessity, connexion_, and _productive quality_, are
all nearly synonymous; and therefore 'tis an absurdity to employ any
of them in defining the rest. By this observation we reject at once
all the vulgar definitions which philosophers have given of power and
efficacy; and instead of searching for the idea in these definitions,
must look for it in the impressions from which it is originally
derived. If it be a compound idea, it must arise from compound
impressions. If simple, from simple impressions.
I believe the most general and most popular explication of this
matter, is to say,[13] that finding from experience that there are
several new productions in matter, such as the motions and variations
of body, and concluding that there must somewhere be a power capable
of producing them, we arrive at last by this reasoning at the idea
of power and efficacy. But to be convinced that this explication is
more popular than philosophical, we need but reflect on two very
obvious principles. _First_, that reason alone can never give rise
to any original idea; and, _secondly_, that reason, as distinguished
from experience, can never make us conclude that a cause or productive
quality is absolutely requisite to every beginning of existence. Both
these considerations have been sufficiently explained; and therefore
shall not at present be any farther insisted on.
I shall only infer from them, that since reason can never give rise
to the idea of efficacy, that idea must be derived from experience,
and from some particular instances of this efficacy, which make
their passage into the mind by the common channels of sensation or
reflection. Ideas always represent their objects or impressions;
and _vice versa_, there are some objects necessary to give rise to
every idea. If we pretend, therefore, to have any just idea of this
efficacy, we must produce some instance wherein the efficacy is
plainly discoverable to the mind, and its operations obvious to our
consciousness or sensation. By the refusal of this, we acknowledge,
that the idea is impossible and imaginary; since the principle of
innate ideas, which alone can save us from this dilemma, has been
already refuted, and is now almost universally rejected in the learned
world. Our present business, then, must be to find some natural
production, where the operation and efficacy of a cause can be clearly
conceived and comprehended by the mind, without any danger of obscurity
or mistake.
In this research, we meet with very little encouragement from
that prodigious diversity which is found in the opinions of those
philosophers who have pretended to explain the secret force and
energy of causes.[14] There are some who maintain, that bodies operate
by their substantial form; others, by their accidents or qualities;
several, by their matter and form; some, by their form and accidents;
others, by certain virtues and faculties distinct from all this.
All these sentiments, again, are mixed and varied in a thousand
different ways, and form a strong presumption that none of them have
any solidity or evidence, and that the supposition of an efficacy in
any of the known qualities of matter is entirely without foundation.
This presumption must increase upon us, when we consider, that these
principles of substantial forms, and accidents, and faculties, are not
in reality any of the known properties of bodies, but are perfectly
unintelligible and inexplicable. For 'tis evident philosophers would
never have had recourse to such obscure and uncertain principles, had
they met with any satisfaction in such as are clear and intelligible;
especially in such an affair as this, which must be an object of the
simplest understanding, if not of the senses. Upon the whole, we may
conclude, that 'tis impossible, in any one instance, to show the
principle in which the force and agency of a cause is placed; and
that the most refined and most vulgar understandings are equally at
a loss in this particular. If any one think proper to refute this
assertion, he need not put himself to the trouble of inventing any long
reasonings, but may at once show us an instance of a cause, where we
discover the power or operating principle. This defiance we are obliged
frequently to make use of, as being almost the only means of proving a
negative in philosophy.
The small success which has been met with in all the attempts to fix
this power, has at last obliged philosophers to conclude, that the
ultimate force and efficacy of nature is perfectly unknown to us,
and that 'tis in vain we search for it in all the known qualities of
matter. In this opinion they are almost unanimous; and 'tis only in
the inference they draw from it, that they discover any difference in
their sentiments. For some of them, as the Cartesians in particular,
having established it as a principle, that we are perfectly acquainted
with the essence of matter, have very naturally inferred, that it is
endowed with no efficacy, and that 'tis impossible for it of itself to
communicate motion, or produce any of those effects, which we ascribe
to it. As the essence of matter consists in extension, and as extension
implies not actual motion, but only mobility; they conclude, that the
energy, which produces the motion, cannot lie in the extension.
This conclusion leads them into another, which they regard as perfectly
unavoidable. Matter, say they, is in itself entirely unactive, and
deprived of any power, by which it may produce, or continue, or
communicate motion: but since these effects are evident to our senses,
and since the power that produces them must be placed somewhere, it
must lie in the Deity, or that Divine Being who contains in his nature
all excellency and perfection. 'Tis the Deity, therefore, who is the
prime mover of the universe, and who not only first created matter, and
gave it its original impulse, but likewise, by a continued exertion of
omnipotence, supports its existence, and successively bestows on it
all those motions, and configurations, and qualities, with which it is
endowed.
This opinion is certainly very curious, and well worth our attention;
but 'twill appear superfluous to examine it in this place, if we
reflect a moment on our present purpose in taking notice of it. We
have established it as a principle, that as all ideas are derived
from impressions, or some precedent _perceptions_,'tis impossible we
can have any idea of power and efficacy, unless some instances can
be produced, wherein this power _is perceived_ to exert itself. Now,
as these instances can never be discovered in body, the Cartesians,
proceeding upon their principle of innate ideas, have had recourse
to a Supreme Spirit or Deity, whom they consider as the only active
being in the universe, and as the immediate cause of every alteration
in matter. But the principle of innate ideas being allowed to be
false, it follows, that the supposition of a Deity can serve us in no
stead, in accounting for that idea of agency, which we search for in
vain in all the objects which are presented to our senses, or which
we are internally conscious of in our own minds. For if every idea
be derived from an impression, the idea of a Deity proceeds from the
same origin; and if no impression, either of sensation or reflection,
implies any force or efficacy, 'tis equally impossible to discover
or even imagine any such active principle in the Deity. Since these
philosophers, therefore, have concluded that matter cannot be endowed
with any efficacious principle, because 'tis impossible to discover
in it such a principle, the same course of reasoning should determine
them to exclude it from the Supreme Being, or, if they esteem that
opinion absurd and impious, as it really is, I shall tell them how they
may avoid it; and that is, by concluding from the very first, that
they have no adequate idea of power or efficacy in any object; since
neither in body nor spirit, neither in superior nor inferior natures,
are they able to discover one single instance of it.
The same conclusion is unavoidable upon the hypothesis of those, who
maintain the efficacy of second causes, and attribute a derivative, but
a real power and energy to matter. For as they confess that this energy
lies not in any of the known qualities of matter, the difficulty still
remains concerning the origin of its idea. If we have really an idea
of power, we may attribute power to an unknown quality: but as 'tis
impossible that that idea can be derived from such a quality, and as
there is nothing in known qualities which can produce it, it follows
that we deceive ourselves, when we imagine we are possessed of any idea
of this kind, after the manner we commonly understand it. All ideas are
derived from, and represent impressions. We never have any impression
that contains any power or efficacy. We never, therefore, have any idea
of power.
Some have asserted, that we feel an energy or power in our own mind;
and that, having in this manner acquired the idea of power, we transfer
that quality to matter, where we are not able immediately to discover
it. The motions of our body, and the thoughts and sentiments of our
mind (say they) obey the will; nor do we seek any farther to acquire
a just notion of force or power. But to convince us how fallacious
this reasoning is, we need only consider, that the will being here
considered as a cause, has no more a discoverable connexion with its
effects, than any material cause has with its proper effect. So far
from perceiving the connexion betwixt an act of volition and a motion
of the body, 'tis allowed that no effect is more inexplicable from
the powers and essence of thought and matter. Nor is the empire
of the will over our mind more intelligible. The effect is there
distinguishable and separable from the cause, and could be foreseen
without the experience of their constant conjunction. We have command
over our mind to a certain degree, but beyond _that_ lose all empire
over it: and 'tis evidently impossible to fix any precise bounds to
our authority, where we consult not experience. In short, the actions
of the mind are, in this respect, the same with those of matter. We
perceive only their constant conjunction; nor can we ever reason beyond
it. No internal impression has an apparent energy, more than external
objects have. Since, therefore, matter is confessed by philosophers to
operate by an unknown force, we should in vain hope to attain an idea
of force by consulting our own minds.[15]
It has been established as a certain principle, that general or
abstract ideas are nothing but individual ones taken in a certain
light, and that, in reflecting on any object, 'tis as impossible to
exclude from our thought all particular degrees of quantity and quality
as from the real nature of things. If we be possessed, therefore, of
any idea of power in general, we must also be able to conceive some
particular species of it; and as power cannot subsist alone, but is
always regarded as an attribute of some being or existence, we must
be able to place this power in some particular being, and conceive
that being as endowed with a real force and energy, by which such a
particular effect necessarily results from its operation. We must
distinctly and particularly conceive the connexion betwixt the cause
and effect, and be able to pronounce, from a simple view of the one,
that it must be followed or preceded by the other. This is the true
manner of conceiving a particular power in a particular body: and a
general idea being impossible without an individual; where the latter
is impossible, 'tis certain the former can never exist. Now nothing
is more evident, than that the human mind cannot form such an idea of
two objects, as to conceive any connexion betwixt them, or comprehend
distinctly that power or efficacy, by which they are united. Such a
connexion would amount to a demonstration, and would imply the absolute
impossibility for the one object not to follow, or to be conceived not
to follow upon the other: which kind of connexion has already been
rejected in all cases. If any one is of a contrary opinion, and thinks
he has attained a notion of power in any particular object, I desire he
may point out to me that object. But till I meet with such a one, which
I despair of, I cannot forbear concluding, that since we can never
distinctly conceive how any particular power can possibly reside in any
particular object, we deceive ourselves in imagining we can form any
such general idea.
Thus, upon the whole, we may infer, that when we talk of any being,
whether of a superior or inferior nature, as endowed with a power
or force, proportioned to any effect; when we speak of a necessary
connexion betwixt objects, and suppose that this connexion depends upon
an efficacy or energy, with which any of these objects are endowed; in
all the expressions, _so applied_, we have really no distinct meaning,
and make use only of common words, without any clear and determinate
ideas. But as 'tis more probable, that these expressions do here lose
their true meaning by being _wrong applied_, than that they never have
any meaning; 'twill be proper to bestow another consideration on this
subject, to see if possibly we can discover the nature and origin of
those ideas we annex to them.
Suppose two objects to be presented to us, of which the one is the
cause and the other the effect; 'tis plain that, from the simple
consideration of one, or both these objects, we never shall perceive
the tie by which they are united, or be able certainly to pronounce,
that there is a connexion betwixt them. 'Tis not, therefore, from any
one instance, that we arrive at the idea of cause and effect, of a
necessary connexion of power, of force, of energy, and of efficacy.
Did we never see any but particular conjunctions of objects, entirely
different from each other, we should never be able to form any such
ideas.
But, again, suppose we observe several instances in which the same
objects are always conjoined together, we immediately conceive a
connexion betwixt them, and begin to draw an inference from one
to another. This multiplicity of resembling instances, therefore,
constitutes the very essence of power or connexion, and is the source
from which the idea of it arises. In order, then, to understand the
idea of power, we must consider that multiplicity; nor do I ask more
to give a solution of that difficulty, which has so long perplexed
us. For thus I reason. The repetition of perfectly similar instances
can never _alone_ give rise to an original idea, different from what
is to be found in any particular instance, as has been observed, and
as evidently follows from our fundamental principle, _that all ideas
are copied from impressions_. Since, therefore, the idea of power is
a new original idea, not to be found in any one instance, and which
yet arises from the repetition of several instances, it follows, that
the repetition _alone_ has not that effect, but must either _discover_
or _produce_ something new, which is the source of that idea. Did the
repetition neither discover nor produce any thing new, our ideas might
be multiplied by it, but would not be enlarged above what they are upon
the observation of one single instance. Every enlargement, therefore,
(such as the idea of power or connexion) which arises from the
multiplicity of similar instances, is copied from some effects of the
multiplicity, and will be perfectly understood by understanding these
effects. Wherever we find any thing new to be discovered or produced by
the repetition, there we must place the power, and must never look for
it in any other object.
But 'tis evident, in the first place, that the repetition of like
objects in like relations of succession and contiguity, _discovers_
nothing new in any one of them; since we can draw no inference from
it, nor make it a subject either of our demonstrative or probable
reasonings; as has been already proved.[16] Nay, suppose we could draw
an inference, 'twould be of no consequence in the present case; since
no kind of reasoning can give rise to a new idea, such as this of power
is; but wherever we reason, we must antecedently be possessed of clear
ideas, which may be the objects of our reasoning. The conception always
precedes the understanding; and where the one is obscure, the other is
uncertain; where the one fails, the other must fail also.
Secondly, 'tis certain that this repetition of similar objects in
similar situations, _produces_ nothing new either in these objects, or
in any external body. For 'twill readily be allowed, that the several
instances we have of the conjunction of resembling causes and effects,
are in themselves entirely independent, and that the communication of
motion, which I see result at present from the shock of two billiard
balls, is totally distinct from that which I saw result from such an
impulse a twelvemonth ago. These impulses have no influence on each
other. They are entirely divided by time and place; and the one might
have existed and communicated motion, though the other never had been
in being.
There is, then, nothing new either discovered or produced in any
objects by their constant conjunction, and by the uninterrupted
resemblance of their relations of succession and contiguity. But 'tis
from this resemblance, that the ideas of necessity, of power, and of
efficacy, are derived. These ideas therefore represent not any thing,
that does or can belong to the objects, which are constantly conjoined.
This is an argument, which, in every view we can examine it, will be
found perfectly unanswerable. Similar instances are still the first
source of our idea of power or necessity; at the same time that they
have no influence by their similarity either on each other, or on any
external object. We must therefore turn ourselves to some other quarter
to seek the origin of that idea.
Though the several resembling instances, which give rise to the idea
of power, have no influence on each other, and can never produce any
new quality _in the object_, which can be the model of that idea,
yet the _observation_ of this resemblance produces a new impression
_in the mind_, which is its real model. For after we have observed
the resemblance in a sufficient number of instances, we immediately
feel a determination of the mind to pass from one object to its usual
attendant, and to conceive it in a stronger light upon account of that
relation. This determination is the only effect of the resemblance;
and therefore must be the same with power or efficacy, whose idea is
derived from the resemblance. The several instances of resembling
conjunctions lead us into the notion of power and necessity. These
instances are in themselves totally distinct from each other, and have
no union but in the mind, which observes them, and collects their
ideas. Necessity, then, is the effect of this observation, and as
nothing but an internal impression of the mind, or a determination to
carry our thoughts from one object to another. Without considering it
in this view, we can never arrive at the most distant notion of it,
or be able to attribute it either to external or internal objects, to
spirit or body, to causes or effects.
The necessary connexion betwixt causes and effects is the foundation of
our inference from one to the other. The foundation of our inference is
the transition arising from the accustomed union. These are therefore
the same.
The idea of necessity arises from some impression. There is no
impression conveyed by our senses, which can give rise to that idea.
It must, therefore, be derived from some internal impression, or
impression of reflection. There is no internal impression which has any
relation to the present business, but that propensity, which custom
produces, to pass from an object to the idea of its usual attendant.
This, therefore, is the essence of necessity. Upon the whole, necessity
is something that exists in the mind, not in objects; nor is it
possible for us ever to form the most distant idea of it, considered as
a quality in bodies. Either we have no idea of necessity, or necessity
is nothing but that determination of the thought to pass from causes
to effects, and from effects to causes, according to their experienced
union.
Thus, as the necessity, which makes two times two equal to four, or
three angles of a triangle equal to two right ones, lies only in the
act of the understanding, by which we consider and compare these
ideas; in like manner, the necessity of power, which unites causes and
effects, lies in the determination of the mind to pass from the one to
the other. The efficacy or energy of causes is neither placed in the
causes themselves, nor in the Deity, nor in the concurrence of these
two principles; but belongs entirely to the soul, which considers the
union of two or more objects in all past instances. 'Tis here that
the real power of causes is placed, along with their connexion and
necessity.
I am sensible, that of all the paradoxes which I have had, or shall
hereafter have occasion to advance in the course of this Treatise,
the present one is the most violent, and that 'tis merely by dint of
solid proof and reasoning I can ever hope it will have admission, and
overcome the inveterate prejudices of mankind. Before we are reconciled
to this doctrine, how often must we repeat to ourselves, _that_ the
simple view of any two objects or actions, however related, can never
give us any idea of power, or of a connexion betwixt them: _that_ this
idea arises from the repetition of their union: _that_ the repetition
neither discovers nor causes any thing in the objects, but has an
influence only on the mind, by that customary transition it produces:
_that_ this customary transition is therefore the same with the power
and necessity; which are consequently qualities of perceptions, not
of objects, and are internally felt by the soul, and not perceived
externally in bodies? There is commonly an astonishment attending every
thing extraordinary; and this astonishment changes immediately into
the highest degree of esteem or contempt, according as we approve or
disapprove of the subject. I am much afraid, that though the foregoing
reasoning appears to me the shortest and most decisive imaginable, yet,
with the generality of readers, the bias of the mind will prevail, and
give them a prejudice against the present doctrine.
This contrary bias is easily accounted for. 'Tis a common observation,
that the mind has a great propensity to spread itself on external
objects, and to conjoin with them any internal impressions which they
occasion, and which always make their appearance at the same time that
these objects discover themselves to the senses. Thus, as certain
sounds and smells are always found to attend certain Visible objects,
we naturally imagine a conjunction, even in place, betwixt the objects
and qualities, though the qualities be of such a nature as to admit
of no such conjunction, and really exist no where. But of this more
fully hereafter.[17] Meanwhile, 'tis sufficient to observe, that the
same propensity is the reason why we suppose necessity and power to
lie in the objects we consider, not in our mind, that considers them;
notwithstanding it is not possible for us to form the most distant idea
of that quality, when it is not taken for the determination of the mind
to pass from the idea of an object to that of its usual attendant.
But though this be the only reasonable account we can give of
necessity, the contrary notion is so riveted in the mind from the
principles above-mentioned, that I doubt not but my sentiments will
be treated by many as extravagant and ridiculous. What! the efficacy
of causes lie in the determination of the mind! As if causes did not
operate entirely independent of the mind, and would not continue their
operation, even though there was no mind existent to contemplate them,
or reason concerning them. Thought may well depend on causes for its
operation, but not causes on thought. This is to reverse the order of
nature, and make that secondary, which is really primary. To every
operation there is a power proportioned; and this power must be placed
on the body that operates. If we remove the power from one cause, we
must ascribe it to another: but to remove it from all causes, and
bestow it on a being that is no ways related to the cause or effect,
but by perceiving them, is a gross absurdity, and contrary to the most
certain principles of human reason.
I can only reply to all these arguments, that the case is here much the
same, as if a blind man should pretend to find a great many absurdities
in the supposition, that the colour of scarlet is not the same with the
sound of a trumpet, nor light the same with solidity. If we have really
no idea of a power or efficacy in any object, or of any real connexion
betwixt causes and effects, 'twill be to little purpose to prove,
that an efficacy is necessary in all operations. We do not understand
our own meaning in talking so, but ignorantly confound ideas which
are entirely distinct from each other. I am, indeed, ready to allow,
that there may be several qualities, both in material and immaterial
objects, with which we are utterly unacquainted; and if we please to
call these _power_ or _efficacy_,'twill be of little consequence to the
world. But when, instead of meaning these unknown qualities, we make
the terms of power and efficacy signify something, of which we have a
clear idea, and which is incompatible with those objects to which we
apply it, obscurity and error begin then to take place, and we are led
astray by a false philosophy. This is the case when we transfer the
determination of the thought to external objects, and suppose any real
intelligible connexion betwixt them; that being a quality which can
only belong to the mind that considers them.
As to what may be said, that the operations of nature are independent
of our thought and reasoning, I allow it; and accordingly have
observed, that objects bear to each other the relations of contiguity
and succession; that like objects may be observed, in several
instances, to have like relations; and that all this is independent
of, and antecedent to, the operations of the understanding. But if we
go any farther, and ascribe a power or necessary connexion to these
objects, this is what we can never observe in them, but must draw the
idea of it from what we feel internally in contemplating them. And this
I carry so far, that I am ready to convert my present reasoning into
an instance of it, by a subtility which it will not be difficult to
comprehend.
When any object is presented to us, it immediately conveys to the mind
a lively idea of that object which is usually found to attend it; and
this determination of the mind forms the necessary connexion of these
objects. But when we change the point of view from the objects to the
perceptions, in that case the impression is to be considered as the
cause, and the lively idea as the effect; and their necessary connexion
is that new determination, which we feel to pass from the idea of the
one to that of the other. The uniting principle among our internal
perceptions is as unintelligible as that among external objects, and
is not known to us any other way than by experience. Now, the nature
and effects of experience have been already sufficiently examined and
explained. It never gives us any insight into the internal structure
or operating principle of objects, but only accustoms the mind to pass
from one to another.
'Tis now time to collect all the different parts of this reasoning,
and, by joining them together, form an exact definition of the
relation of cause and effect, which makes the subject of the present
inquiry. This order would not have been excusable, of first examining
our inference from the relation before we had explained the relation
itself, had it been possible to proceed in a different method. But as
the nature of the relation depends so much on that of the inference,
we have been obliged to advance in this seemingly preposterous manner,
and make use of terms before we were able exactly to define them, or
fix their meaning. We shall now correct this fault by giving a precise
definition of cause and effect.
There may two definitions be given of this relation, which are only
different by their presenting a different view of the same object, and
making us consider it either as a _philosophical_ or as a _natural_
relation; either as a comparison of two ideas, or as an association
betwixt them. We may define a _cause_ to be "An object precedent and
contiguous to another, and where all the objects resembling the former
are placed in like relations of precedency and contiguity to those
objects that resemble the latter." If this definition be esteemed
defective, because drawn from objects foreign to the cause, we may
substitute this other definition in its place, viz. "A _cause_ is an
object precedent and contiguous to another, and so united with it that
the idea of the one determines the mind to form the idea of the other,
and the impression of the one to form a more lively idea of the other."
Should this definition also be rejected for the same reason, I know no
other remedy, than that the persons who express this delicacy should
substitute a juster definition in its place. But, for my part, I must
own my incapacity for such an undertaking. When I examine, with the
utmost accuracy, those objects which are commonly denominated causes
and effects, I find, in considering a single instance, that the one
object is precedent and contiguous to the other; and in enlarging my
view to consider several instances, I find only that like objects are
constantly placed in like relations of succession and contiguity.
Again, when I consider the influence of this constant conjunction, I
perceive that such a relation can never be an object of reasoning,
and can never operate upon the mind but by means of custom, which
determines the imagination to make a transition from the idea of one
object to that of its usual attendant, and from the impression of
one to a more lively idea of the other. However extraordinary these
sentiments may appear, I think it fruitless to trouble myself with any
farther inquiry or reasoning upon the subject, but shall repose myself
on them as on established maxims.
'Twill only be proper, before we leave this subject, to draw some
corollaries from it, by which we may remove several prejudices and
popular errors that have very much prevailed in philosophy. First,
we may learn, from the foregoing doctrine, that all causes are of
the same kind, and that, in particular, there is no foundation for
that distinction which we sometimes make betwixt efficient causes,
and causes _sine qua non_; or betwixt efficient causes, and formal,
and material, and exemplary, and final causes. For as our idea of
efficiency is derived from the constant conjunction of two objects,
wherever this is observed, the cause is efficient; and where it is not,
there can never be a cause of any kind. For the same reason we must
reject the distinction betwixt _cause_ and _occasion_, when supposed to
signify any thing essentially different from each other. If constant
conjunction be implied in what we call occasion, 'tis a real cause; if
not, 'tis no relation at all, and cannot give rise to any argument or
reasoning.
Secondly, the same course of reasoning will make us conclude, that
there is but one kind of _necessity_, as there is but one kind of
cause, and that the common distinction betwixt _moral_ and _physical_
necessity is without any foundation in nature. This clearly appears
from the precedent explication of necessity. 'Tis the constant
conjunction of objects, along with the determination of the mind, which
constitutes a physical necessity: and the removal of these is the same
thing with _chance_. As objects must either be conjoined or not, and as
the mind must either be determined or not to pass from one object to
another, 'tis impossible to admit of any medium betwixt chance and an
absolute necessity. In weakening this conjunction and determination you
do not change the nature of the necessity; since even in the operation
of bodies, these have different degrees of constancy and force, without
producing a different species of that relation.
The distinction, which we often make betwixt _power_ and the _exercise_
of it, is equally without foundation.
Thirdly, we may now be able fully to overcome all that repugnance,
which 'tis so natural for us to entertain against the foregoing
reasoning, by which we endeavoured to prove, that the necessity of a
cause to every beginning of existence is not founded on any arguments
either demonstrative or intuitive. Such an opinion will not appear
strange after the foregoing definitions. If we define a cause to be _an
object precedent and contiguous to another, and where all the objects
resembling the former are placed in a like relation of priority and
contiguity to those objects that resemble the latter_; we may easily
conceive that there is no absolute nor metaphysical necessity, that
every beginning of existence should be attended with such an object.
If we define a cause to be, _an object precedent and contiguous to
another, and so united with it in the imagination, that the idea of
the one determines the mind to form the idea of the other, and the
impression of the one to form a more lively idea of the other_; we
shall make still less difficulty of assenting to this opinion. Such
an influence on the mind is in itself perfectly extraordinary and
incomprehensible; nor can we be certain of its reality, but from
experience and observation.
I shall add as a fourth corollary, that we can never have reason to
believe that any object exists, of which we cannot form an idea.
For, as all our reasonings concerning existence are derived from
causation, and as all our reasonings concerning causation are derived
from the experienced conjunction of objects, not from any reasoning or
reflection, the same experience must give us a notion of these objects,
and must remove all mystery from our conclusions. This is so evident
that 'twould scarce have merited our attention, were it not to obviate
certain objections of this kind which might arise against the following
reasonings concerning _matter_ and _substance_. I need not observe,
that a full knowledge of the object is not requisite, but only of those
qualities of it which we believe to exist.
[12] Sect. 2.
[13] See Mr Locke; chapter of Power.
[14] See Father Malebranche, Book VI. Part II. Chap. 3, and the
illustrations upon it.
[15] The same imperfection attends our ideas of the Deity; but this can
have no effect either on religion or morals. The order of the universe
proves an omnipotent mind; that is, a mind whose will is _constantly
attended_ with the obedience of every creature and being. Nothing more
is requisite to give a foundation to all the articles of religion; nor
is it necessary we should form a distinct idea of the force and energy
of the Supreme Being.
[16] Section 6.
[17] Part IV. sect 5.