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distinctness; as if ever so conformable to reality。 is no less intelligible a
proposition; and implies no more contradiction than the
affirmation; 。 We should in vain;
therefore; attempt to demonstrate its falsehood。 Were it
demonstratively false; it would imply a contradiction; and
could never be distinctly conceived by the mind。
It may; therefore; be a subject worthy of curiosity; to
enquire what is the nature of that evidence which assures us
of any real existence and matter of fact; beyond the present
testimony of our senses; or the records of our memory。 This
part of philosophy; it is observable; has been little
cultivated; either by the ancients or moderns; and therefore
our doubts and errors; in the prosecution of so important an
enquiry; may be the more excusable; while we march through
such difficult paths without any guide or direction。 They
may even prove useful; by exciting curiosity; and destroying
that implicit faith and security; which is the bane of all
reasoning and free enquiry。 The discovery of defects in the
common philosophy; if any such there be; will not; I
presume; be a discouragement; but rather an incitement; as
is usual; to attempt something more full and satisfactory
than has yet been proposed to the public。
All reasonings concerning matter of fact seem to be
founded on the relation of 。 By means of
that relation alone we can go beyond the evidence of our
memory and senses。 If you were to ask a man; why he believes
any matter of fact; which is absent; for instance; that his
friend is in the country; or in F/RANCE; he would give you
a reason; and this reason would be some other fact; as a
letter received from him; or the knowledge of his former
resolutions and promises。 A man finding a watch or any other
machine in a desert island; would conclude that there had
once been men in that island。 All our reasonings concerning
fact are of the same nature。 And here it is constantly
supposed that there is a connexion between the present fact
and that which is inferred from it。 Were there nothing to
bind them together; the inference would be entirely
precarious。 The hearing of an articulate voice and rational
discourse in the dark assures us of the presence of some
person: Why? because these are the effects of the human make
and fabric; and closely connected with it。 If we anatomize
all the other reasonings of this nature; we shall find that
they are founded on the relation of cause and effect; and
that this relation is either near or remote; direct or
collateral。 Heat and light are collateral effects of fire;
and the one effect may justly be inferred from the other。
If we would satisfy ourselves; therefore; concerning
the nature of that evidence; which assures us of matters of
fact; we must enquire how we arrive at the knowledge of
cause and effect。
I shall venture to affirm; as a general proposition;
which admits of no exception; that the knowledge of this
relation is not; in any instance; attained by reasonings ; but arises entirely from experience; when we find
that any particular objects are constantly conjoined with
each other。 Let an object be presented to a man of ever so
strong natural reason and abilities; if that object be
entirely new to him; he will not be able; by the most
accurate examination of its sensible qualities; to discover
any of its causes or effects。 A/DAM; though his rational
faculties be supposed; at the very first; entirely perfect;
could not have inferred from the fluidity and transparency
of water that it would suffocate him; or from the light and
warmth of fire that it would consume him。 No object ever
discovers; by the qualities which appear to the senses;
either the causes which produced it; or the effects which
will arise from it; nor can our reason; unassisted by
experience; ever draw any inference concerning real
existence and matter of fact。
This proposition; ; will readily
be admitted with regard to such objects; as we remember to
have once been altogether unknown to us; since we must be
conscious of the utter inability; which we then lay under;
of foretelling what would arise from them。 Present two
smooth pieces of marble to a man who has no tincture of
natural philosophy; he will never discover that they will
adhere together in such a manner as to require great force
to separate them in a direct line; while they make so small
a resistance to a lateral pressure。 Such events; as bear
little analogy to the common course of nature; are also
readily confessed to be known only by experience; nor does
any man imagine that the explosion of gunpowder; or the
attraction of a loadstone; could ever be discovered by
arguments 。 In like manner; when an effect is
supposed to depend upon an intricate machinery or secret
structure of parts; we make no difficulty in attributing all
our knowledge of it to experience。 Who will assert that he
can give the ultimate reason; why milk or bread is proper
nourishment for a man; not for a lion or a tyger?
But the same truth may not appear; at first sight; to
have the same evidence with regard to events; which have
become familiar to us from our first appearance in the
world; which bear a close analogy to the whole course of
nature; and which are supposed to depend on the simple
qualities of objects; without any secret structure of parts。
We are apt to imagine that we could discover these effects
by the mere operation of our reason; without experience。 We
fancy; that were we brought on a sudden into this world; we
could at first have inferred that one Billiard…ball would
communicate motion to another upon impulse; and that we
needed not to have waited for the event; in order to
pronounce with certainty concerning it。 Such is the
influence of custom; that; where it is strongest; it not
only covers our natural ignorance; but even conceals itself;
and seems not to take place; merely because it is found in
the highest degree。
But to convince us that all the laws of nature; and all
the operations of bodies without exception; are known only
by experience; the following reflections may; perhaps;
suffice。 Were any object presented to us; and were we
required to pronounce concerning the effect; which will
result from it; without consulting past observation; after
what manner; I beseech you; must the mind proceed in this
operation? It must invent or imagine some event; which it
ascribes to the object as its effect; and it is plain that
this invention must be entirely arbitrary。 The mind can
never possibly find the effect in the supposed cause; by the
most accurate scrutiny and examination。 For the effect is
totally different from the cause; and consequently can never
be discovered in it。 Motion in the second Billiard…ball is a
quite distinct event from motion in the first; nor is there
any thing in the one to suggest the smallest hint of the
other。 A stone or piece of metal raised into the air; and
left without any support; immediately falls: But to consider
the matter ; is there any thing we discover in
this situation which can beget the idea of a downward;
rather than an upward; or any other motion; in the stone or
metal?
And as the first imagination or invention of a
particular effect; in all natural operations; is arbitrary;
where we consult not experience; so must we also esteem the
supposed tie or connexion between the cause and effect;
which binds them together; and renders it impossible that
any other effect could result from the operation of that
cause。 When I see; for instance; a Billiard…ball moving in a
straight line towards another; even suppose motion in the
second ball should by accident be suggested to me; as the
result of their contact or impulse; may I not conceive; that
a hundred different events might as well follow from that
cause? May not both these balls remain at absolute rest? May
not the first ball return in a straight line; or leap off
from the second in any line or direction? All these
suppositions are consistent and conceivable。 Why then should
we give the preference to one; which is no more consistent
or conceivable than the rest? All our reasonings
will never be able to show us any foundation for this
preference。
In a word; then; every effect is a distinct event from
its cause。 It could not; therefore; be discovered in the
cause; and the first invention or conception of it; ; must be entirely arbitrary。 And even after it is
suggested; the conjunction of it with the cause must appear
equally arbitrary; since there are always many other
effects; which; to reason; must seem fully as consistent and
natural。 In vain; therefore; should we pretend to determine
any single event; or infer any cause or effect; without the
assistance of observation and experience。
Hence we may discover the reason why no philosopher;
who is rational and modest; has ever pretended to assign the
ultimate cause of any natural operation; or to