SECTION III.: Why a cause is always necessary.
To begin with the first question concerning the necessity of a cause: ’Tis a general maxim in philosophy, that whatever begins to exist, must have a cause of existence. This is commonly
taken for granted in all reasonings, without any proof given or
demanded. ’Tis suppos’d to be founded on intuition, and to be one of
those maxims, which tho’ they may be deny’d with the lips, ’tis
impossible for men in their hearts really to doubt of. But if we examine
this maxim by the idea of knowledge above-explain’d, we shall discover
in it no mark of any such intuitive certainty; but on the contrary shall
find, that ’tis of a nature quite foreign to that species of
conviction.
All certainty arises
from the comparison of ideas, and from the discovery of such relations
as are unalterable, so long as the ideas continue the same. These
relations are resemblance, proportions in quantity and number, degrees of any quality, and contrariety; none of which are imply’d in this proposition, Whatever has a beginning has also a cause of existence.
That proposition therefore is not intuitively certain. At least any
one, who wou’d assert it to be intuitively certain, must deny these to
be the only infallible relations, and must find some other relation of
that kind to be imply’d in it; which it will then be time enough to
examine.
But here is an
argument, which proves at once, that the foregoing proposition is
neither intuitively nor demonstrably certain. We can never demonstrate
the necessity of a cause to every new existence, or new modification of
existence, without shewing at the same time the impossibility there is,
that any thing can ever begin to exist without some productive
principle; and where the latter proposition cannot be prov’d, we must
despair of ever being able to prove the former. Now that the latter
proposition is utterly incapable of a demonstrative proof, we may
satisfy ourselves by considering, that as all distinct ideas are
separable from each other, and as the ideas of cause and effect are
evidently distinct, ’twill be easy for us to conceive any object to be
non-existent this moment, and existent the next, without conjoining to
it the distinct idea of a cause or productive principle. The separation,
therefore, of the idea of a cause from
that of a beginning of existence, is plainly possible for the
imagination; and consequently the actual separation of these objects is
so far possible, that it implies no contradiction nor absurdity; and is
therefore incapable of being refuted by any reasoning from mere ideas;
without which ’tis impossible to demonstrate the necessity of a cause.
Accordingly we shall
find upon examination, that every demonstration, which has been produc’d
for the necessity of a cause, is fallacious and sophistical. All the
points of time and place,1
say some philosophers, in which we can suppose any object to begin to
exist, are in themselves equal; and unless there be some cause, which is
peculiar to one time and to one place, and which by that means
determines and fixes the existence, it must remain in eternal suspence;
and the object can never begin to be, for want of something to fix its
beginning. But I ask; Is there any more difficulty in supposing the time
and place to be fix’d without a cause, than to suppose the existence to
be determin’d in that manner? The first question that occurs on this
subject is always, whether the object shall exist or not: The next, when and where
it shall begin to exist. If the removal of a cause be intuitively
absurd in the one case, it must be so in the other: And if that
absurdity be not clear without a proof in the one case, it will equally
require one in the other. The absurdity, then, of the one supposition
can never be a proof of that of the other; since they are both upon the
same footing, and must stand or fall by the same reasoning.
The second argument, which
I find us’d on this head, labours under an equal difficulty. Every
thing, ’tis said, must have a cause; for if any thing wanted a cause, it wou’d produce itself;
that is, exist before it existed; which is impossible. But this
reasoning is plainly unconclusive; because it supposes, that in our
denial of a cause we still grant what we expressly deny, viz. that there must be a cause; which therefore is taken to be the object itself; and that, no doubt, is
an evident contradiction. But to say that any thing is produc’d, or to
express myself more properly, comes into existence, without a cause, is
not to affirm, that ’tis itself its own cause; but on the contrary in
excluding all external causes, excludes a fortiori
the thing itself which is created. An object, that exists absolutely
without any cause, certainly is not its own cause; and when you assert,
that the one follows from the other, you suppose the very point in
question, and take it for granted, that ’tis utterly impossible any
thing can ever begin to exist without a cause, but that upon the
exclusion of one productive principle, we must still have recourse to
another.
’Tis exactly the same case with the third
argument, which has been employ’d to demonstrate the necessity of a
cause. Whatever is produc’d without any cause, is produc’d by nothing;
or in other words, has nothing for its cause. But nothing can never be a
cause, no more than it can be something, or equal to two right angles.
By the same intuition, that we perceive nothing not to be equal to two
right angles, or not to be something, we perceive, that it can never be a
cause; and consequently must perceive, that every object has a real
cause of its existence.
I believe it will not
be necessary to employ many words in shewing the weakness of this
argument, after what I have said of the foregoing. They are all of them
founded on the same fallacy, and are deriv’d from the same turn of
thought. ’Tis sufficient only to observe, that when we exclude all
causes we really do exclude them, and neither suppose nothing nor the
object itself to be the causes of the existence; and consequently can
draw no argument from the absurdity of these suppositions to prove the
absurdity of that exclusion. If every thing must have a cause, it
follows, that upon the exclusion of other causes we must accept of the
object itself or of nothing as causes. But ’tis the very point in
question, whether every thing must have a cause or not; and therefore, according to all just reasoning, it ought never to be taken for granted.
They are still more
frivolous, who say, that every effect must have a cause, because ’tis
imply’d in the very idea of effect. Every effect necessarily
pre-supposes a cause; effect being a relative term, of which cause is
the correlative. But this does not prove, that every being must be
preceded by a cause; no more than it follows, because every husband must
have a wife, that therefore every man must be marry’d. The true state
of the question is, whether every object, which begins to exist, must
owe its existence to a cause; and this I assert neither to be
intuitively nor demonstratively certain, and hope to have prov’d it
sufficiently by the foregoing arguments.
http://oll.libertyfund.org/titles/hume-a-treatise-of-human-nature
