Kant established this rather convincingly in the Critique of Pure Reason - the major factor is the fact that, while the cosmological argument can demonstrate the possibility of a first cause, it cannot demonstrate its necessity. In order to demonstrate that a first cause is necessary, and not merely possible, one must assert its existence in another way. The only known way is the ontological argument, which fails horribly.
SECTION V. Of the Impossibility of a Cosmological Proof
of the Existence of God.
It was by no means a natural course of proceeding, but, on the
contrary, an invention entirely due to the subtlety of the schools,
to attempt to draw from a mere idea a proof of the existence of an
object corresponding to it. Such a course would never have been pursued,
were it not for that need of reason which requires it to suppose the
existence of a necessary being as a basis for the empirical regress,
and that, as this necessity must be unconditioned and a priori, reason
is bound to discover a conception which shall satisfy, if possible,
this requirement, and enable us to attain to the a priori cognition
of such a being. This conception was thought to be found in the idea
of an ens realissimum, and thus this idea was employed for the attainment
of a better defined knowledge of a necessary being, of the existence
of which we were convinced, or persuaded, on other grounds. Thus
reason was seduced from her natural courage; and, instead of
concluding with the conception of an ens realissimum, an attempt was
made to begin with it, for the purpose of inferring from it that
idea of a necessary existence which it was in fact called in to
complete. Thus arose that unfortunate ontological argument, which
neither satisfies the healthy common sense of humanity, nor sustains
the scientific examination of the philosopher.
The cosmological proof, which we are about to examine, retains the
connection between absolute necessity and the highest reality; but,
instead of reasoning from this highest reality to a necessary
existence, like the preceding argument, it concludes from the given
unconditioned necessity of some being its unlimited reality. The track
it pursues, whether rational or sophistical, is at least natural,
and not only goes far to persuade the common understanding, but
shows itself deserving of respect from the speculative intellect;
while it contains, at the same time, the outlines of all the arguments
employed in natural theology--arguments which always have been, and
still will be, in use and authority. These, however adorned, and hid
under whatever embellishments of rhetoric and sentiment, are at bottom
identical with the arguments we are at present to discuss. This proof,
termed by Leibnitz the argumentum a contingentia mundi, I shall now
lay before the reader, and subject to a strict examination.
It is framed in the following manner: If something exists, an
absolutely necessary being must likewise exist. Now I, at least,
exist. Consequently, there exists an absolutely necessary being. The
minor contains an experience, the major reasons from a general
experience to the existence of a necessary being.* Thus this
argument really begins at experience, and is not completely a
priori, or ontological. The object of all possible experience being
the world, it is called the cosmological proof. It contains no
reference to any peculiar property of sensuous objects, by which
this world of sense might be distinguished from other possible worlds;
and in this respect it differs from the physico-theological proof,
which is based upon the consideration of the peculiar constitution
of our sensuous world.
[*Footnote: This inference is too well known to require more detailed
discussion. It is based upon the spurious transcendental law of
causality, that everything which is contingent has a cause, which,
if itself contingent, must also have a cause; and so on, till the
series of subordinated causes must end with an absolutely necessary
cause, without which it would not possess completeness.]
The proof proceeds thus: A necessary being can be determined only in
one way, that is, it can be determined by only one of all possible
opposed predicates; consequently, it must be completely determined
in and by its conception. But there is only a single conception of
a thing possible, which completely determines the thing a priori: that
is, the conception of the ens realissimum. It follows that the
conception of the ens realissimum is the only conception by and in
which we can cogitate a necessary being. Consequently, a Supreme Being
necessarily exists.
In this cosmological argument are assembled so many sophistical
propositions that speculative reason seems to have exerted in it all
her dialectical skill to produce a transcendental illusion of the most
extreme character. We shall postpone an investigation of this argument
for the present, and confine ourselves to exposing the stratagem by
which it imposes upon us an old argument in a new dress, and appeals
to the agreement of two witnesses, the one with the credentials of
pure reason, and the other with those of empiricism; while, in fact,
it is only the former who has changed his dress and voice, for the
purpose of passing himself off for an additional witness. That it
may possess a secure foundation, it bases its conclusions upon
experience, and thus appears to be completely distinct from the
ontological argument, which places its confidence entirely in pure
a priori conceptions. But this experience merely aids reason in making
one step--to the existence of a necessary being. What the properties
of this being are cannot be learned from experience; and therefore
reason abandons it altogether, and pursues its inquiries in the sphere
of pure conception, for the purpose of discovering what the properties
of an absolutely necessary being ought to be, that is, what among
all possible things contain the conditions (requisita) of absolute
necessity. Reason believes that it has discovered these requisites
in the conception of an ens realissimum--and in it alone, and hence
concludes: The ens realissimum is an absolutely necessary being. But
it is evident that reason has here presupposed that the conception
of an ens realissimum is perfectly adequate to the conception of a
being of absolute necessity, that is, that we may infer the
existence of the latter from that of the former--a proposition which
formed the basis of the ontological argument, and which is now
employed in the support of the cosmological argument, contrary to
the wish and professions of its inventors. For the existence of an
absolutely necessary being is given in conceptions alone. But if I
say: "The conception of the ens realissimum is a conception of this
kind, and in fact the only conception which is adequate to our idea
of a necessary being," I am obliged to admit, that the latter may be
inferred from the former. Thus it is properly the ontological argument
which figures in the cosmological, and constitutes the whole
strength of the latter; while the spurious basis of experience has
been of no further use than to conduct us to the conception of
absolute necessity, being utterly insufficient to demonstrate the
presence of this attribute in any determinate existence or thing.
For when we propose to ourselves an aim of this character, we must
abandon the sphere of experience, and rise to that of pure
conceptions, which we examine with the purpose of discovering
whether any one contains the conditions of the possibility of an
absolutely necessary being. But if the possibility of such a being
is thus demonstrated, its existence is also proved; for we may then
assert that, of all possible beings there is one which possesses the
attribute of necessity--in other words, this being possesses an
absolutely necessary existence.
All illusions in an argument are more easily detected when they
are presented in the formal manner employed by the schools, which we
now proceed to do.
If the proposition: "Every absolutely necessary being is likewise an
ens realissimum," is correct (and it is this which constitutes the
nervus probandi of the cosmological argument), it must, like all
affirmative judgements, be capable of conversion--the conversio per
accidens, at least. It follows, then, that some entia realissima are
absolutely necessary beings. But no ens realissimum is in any
respect different from another, and what is valid of some is valid
of all. In this present case, therefore, I may employ simple
conversion, and say: "Every ens realissimum is a necessary being."
But as this proposition is determined a priori by the conceptions
contained in it, the mere conception of an ens realissimum must
possess the additional attribute of absolute necessity. But this is
exactly what was maintained in the ontological argument, and not
recognized by the cosmological, although it formed the real ground
of its disguised and illusory reasoning.
Thus the second mode employed by speculative reason of demonstrating
the existence of a Supreme Being, is not only, like the first,
illusory and inadequate, but possesses the additional blemish of an
ignoratio elenchi--professing to conduct us by a new road to the
desired goal, but bringing us back, after a short circuit, to the
old path which we had deserted at its call.
I mentioned above that this cosmological argument contains a perfect
nest of dialectical assumptions, which transcendental criticism does
not find it difficult to expose and to dissipate. I shall merely
enumerate these, leaving it to the reader, who must by this time be
well practised in such matters, to investigate the fallacies
residing therein.
The following fallacies, for example, are discoverable in this
mode of proof: 1. The transcendental principle: "Everything that is
contingent must have a cause"--a principle without significance,
except in the sensuous world. For the purely intellectual conception
of the contingent cannot produce any synthetical proposition, like
that of causality, which is itself without significance or
distinguishing characteristic except in the phenomenal world. But in
the present case it is employed to help us beyond the limits of its
sphere. 2. "From the impossibility of an infinite ascending series
of causes in the world of sense a first cause is inferred"; a
conclusion which the principles of the employment of reason do not
justify even in the sphere of experience, and still less when an
attempt is made to pass the limits of this sphere. 3. Reason allows
itself to be satisfied upon insufficient grounds, with regard to the
completion of this series. It removes all conditions (without which,
however, no conception of Necessity can take place); and, as after
this it is beyond our power to form any other conceptions, it
accepts this as a completion of the conception it wishes to form of
the series. 4. The logical possibility of a conception of the total
of reality (the criterion of this possibility being the absence of
contradiction) is confounded with the transcendental, which requires
a principle of the practicability of such a synthesis--a principle
which again refers us to the world of experience. And so on.
The aim of the cosmological argument is to avoid the necessity of
proving the existence of a necessary being priori from mere
conceptions--a proof which must be ontological, and of which we feel
ourselves quite incapable. With this purpose, we reason from an actual
existence--an experience in general, to an absolutely necessary
condition of that existence. It is in this case unnecessary to
demonstrate its possibility. For after having proved that it exists,
the question regarding its possibility is superfluous. Now, when we
wish to define more strictly the nature of this necessary being, we
do not look out for some being the conception of which would enable
us to comprehend the necessity of its being--for if we could do this,
an empirical presupposition would be unnecessary; no, we try to
discover merely the negative condition (conditio sine qua non),
without which a being would not be absolutely necessary. Now this
would be perfectly admissible in every sort of reasoning, from a
consequence to its principle; but in the present case it unfortunately
happens that the condition of absolute necessity can be discovered
in but a single being, the conception of which must consequently
contain all that is requisite for demonstrating the presence of
absolute necessity, and thus entitle me to infer this absolute
necessity a priori. That is, it must be possible to reason conversely,
and say: The thing, to which the conception of the highest reality
belongs, is absolutely necessary. But if I cannot reason thus--and
I cannot, unless I believe in the sufficiency of the ontological
argument--I find insurmountable obstacles in my new path, and am
really no farther than the point from which I set out. The
conception of a Supreme Being satisfies all questions a priori
regarding the internal determinations of a thing, and is for this
reason an ideal without equal or parallel, the general conception of
it indicating it as at the same time an ens individuum among all
possible things. But the conception does not satisfy the question
regarding its existence--which was the purpose of all our inquiries;
and, although the existence of a necessary being were admitted, we
should find it impossible to answer the question: What of all things
in the world must be regarded as such?
It is certainly allowable to admit the existence of an
all-sufficient being--a cause of all possible effects--for the purpose
of enabling reason to introduce unity into its mode and grounds of
explanation with regard to phenomena. But to assert that such a
being necessarily exists, is no longer the modest enunciation of an
admissible hypothesis, but the boldest declaration of an apodeictic
certainty; for the cognition of that which is absolutely necessary
must itself possess that character.
The aim of the transcendental ideal formed by the mind is either
to discover a conception which shall harmonize with the idea of
absolute necessity, or a conception which shall contain that idea.
If the one is possible, so is the other; for reason recognizes that
alone as absolutely necessary which is necessary from its
conception. But both attempts are equally beyond our power--we find
it impossible to satisfy the understanding upon this point, and as
impossible to induce it to remain at rest in relation to this
incapacity.
Unconditioned necessity, which, as the ultimate support and stay
of all existing things, is an indispensable requirement of the mind,
is an abyss on the verge of which human reason trembles in dismay.
Even the idea of eternity, terrible and sublime as it is, as
depicted by Haller, does not produce upon the mental vision such a
feeling of awe and terror; for, although it measures the duration of
things, it does not support them. We cannot bear, nor can we rid
ourselves of the thought that a being, which we regard as the greatest
of all possible existences, should say to himself: I am from
eternity to eternity; beside me there is nothing, except that which
exists by my will; whence then am I? Here all sinks away from under
us; and the greatest, as the smallest, perfection, hovers without stay
or footing in presence of the speculative reason, which finds it as
easy to part with the one as with the other.
Many physical powers, which evidence their existence by their
effects, are perfectly inscrutable in their nature; they elude all
our powers of observation. The transcendental object which forms the
basis of phenomena, and, in connection with it, the reason why our
sensibility possesses this rather than that particular kind of
conditions, are and must ever remain hidden from our mental vision;
the fact is there, the reason of the fact we cannot see. But an
ideal of pure reason cannot be termed mysterious or inscrutable,
because the only credential of its reality is the need of it felt by
reason, for the purpose of giving completeness to the world of
synthetical unity. An ideal is not even given as a cogitable object,
and therefore cannot be inscrutable; on the contrary, it must, as a
mere idea, be based on the constitution of reason itself, and on
this account must be capable of explanation and solution. For the very
essence of reason consists in its ability to give an account, of all
our conceptions, opinions, and assertions--upon objective, or, when
they happen to be illusory and fallacious, upon subjective grounds.
Detection and Explanation of the Dialectical Illusion in
all Transcendental Arguments for the Existence of a
Necessary Being.
Both of the above arguments are transcendental; in other words, they
do not proceed upon empirical principles. For, although the
cosmological argument professed to lay a basis of experience for its
edifice of reasoning, it did not ground its procedure upon the
peculiar constitution of experience, but upon pure principles of
reason--in relation to an existence given by empirical
consciousness; utterly abandoning its guidance, however, for the
purpose of supporting its assertions entirely upon pure conceptions.
Now what is the cause, in these transcendental arguments, of the
dialectical, but natural, illusion, which connects the conceptions
of necessity and supreme reality, and hypostatizes that which cannot
be anything but an idea? What is the cause of this unavoidable step
on the part of reason, of admitting that some one among all existing
things must be necessary, while it falls back from the assertion of
the existence of such a being as from an abyss? And how does reason
proceed to explain this anomaly to itself, and from the wavering
condition of a timid and reluctant approbation--always again
withdrawn--arrive at a calm and settled insight into its cause?
It is something very remarkable that, on the supposition that
something exists, I cannot avoid the inference that something exists
necessarily. Upon this perfectly natural--but not on that account
reliable--inference does the cosmological argument rest. But, let me
form any conception whatever of a thing, I find that I cannot cogitate
the existence of the thing as absolutely necessary, and that nothing
prevents me--be the thing or being what it may--from cogitating its
non-existence. I may thus be obliged to admit that all existing things
have a necessary basis, while I cannot cogitate any single or
individual thing as necessary. In other words, I can never complete
the regress through the conditions of existence, without admitting
the existence of a necessary being; but, on the other hand, I cannot
make a commencement from this being.
If I must cogitate something as existing necessarily as the basis of
existing things, and yet am not permitted to cogitate any individual
thing as in itself necessary, the inevitable inference is that
necessity and contingency are not properties of things themselves-
otherwise an internal contradiction would result; that consequently
neither of these principles are objective, but merely subjective
principles of reason--the one requiring us to seek for a necessary
ground for everything that exists, that is, to be satisfied with no
other explanation than that which is complete a priori, the other
forbidding us ever to hope for the attainment of this completeness,
that is, to regard no member of the empirical world as
unconditioned. In this mode of viewing them, both principles, in their
purely heuristic and regulative character, and as concerning merely
the formal interest of reason, are quite consistent with each other.
The one says: "You must philosophize upon nature," as if there existed
a necessary primal basis of all existing things, solely for the
purpose of introducing systematic unity into your knowledge, by
pursuing an idea of this character--a foundation which is
arbitrarily admitted to be ultimate; while the other warns you to
consider no individual determination, concerning the existence of
things, as such an ultimate foundation, that is, as absolutely
necessary, but to keep the way always open for further progress in
the deduction, and to treat every determination as determined by some
other. But if all that we perceive must be regarded as conditionally
necessary, it is impossible that anything which is empirically given
should be absolutely necessary.
It follows from this that you must accept the absolutely necessary
as out of and beyond the world, inasmuch as it is useful only as a
principle of the highest possible unity in experience, and you
cannot discover any such necessary existence in the would, the
second rule requiring you to regard all empirical causes of unity as
themselves deduced.
The philosophers of antiquity regarded all the forms of nature as
contingent; while matter was considered by them, in accordance with
the judgement of the common reason of mankind, as primal and
necessary. But if they had regarded matter, not relatively--as the
substratum of phenomena, but absolutely and in itself--as an
independent existence, this idea of absolute necessity would have
immediately disappeared. For there is nothing absolutely connecting
reason with such an existence; on the contrary, it can annihilate it
in thought, always and without self-contradiction. But in thought
alone lay the idea of absolute necessity. A regulative principle must,
therefore, have been at the foundation of this opinion. In fact,
extension and impenetrability--which together constitute our
conception of matter--form the supreme empirical principle of the
unity of phenomena, and this principle, in so far as it is empirically
unconditioned, possesses the property of a regulative principle.
But, as every determination of matter which constitutes what is real
in it--and consequently impenetrability--is an effect, which must have
a cause, and is for this reason always derived, the notion of matter
cannot harmonize with the idea of a necessary being, in its
character of the principle of all derived unity. For every one of
its real properties, being derived, must be only conditionally
necessary, and can therefore be annihilated in thought; and thus the
whole existence of matter can be so annihilated or suppressed. If this
were not the case, we should have found in the world of phenomena
the highest ground or condition of unity--which is impossible,
according to the second regulative principle. It follows that
matter, and, in general, all that forms part of the world of sense,
cannot be a necessary primal being, nor even a principle of
empirical unity, but that this being or principle must have its
place assigned without the world. And, in this way, we can proceed
in perfect confidence to deduce the phenomena of the world and their
existence from other phenomena, just as if there existed no
necessary being; and we can at the same time, strive without ceasing
towards the attainment of completeness for our deduction, just as if
such a being--the supreme condition of all existences--were
presupposed by the mind.
These remarks will have made it evident to the reader that the ideal
of the Supreme Being, far from being an enouncement of the existence
of a being in itself necessary, is nothing more than a regulative
principle of reason, requiring us to regard all connection existing
between phenomena as if it had its origin from an all-sufficient
necessary cause, and basing upon this the rule of a systematic and
necessary unity in the explanation of phenomena. We cannot, at the
same time, avoid regarding, by a transcendental subreptio, this formal
principle as constitutive, and hypostatizing this unity. Precisely
similar is the case with our notion of space. Space is the primal
condition of all forms, which are properly just so many different
limitations of it; and thus, although it is merely a principle of
sensibility, we cannot help regarding it as an absolutely necessary
and self-subsistent thing--as an object given a priori in itself. In
the same way, it is quite natural that, as the systematic unity of
nature cannot be established as a principle for the empirical
employment of reason, unless it is based upon the idea of an ens
realissimum, as the supreme cause, we should regard this idea as a
real object, and this object, in its character of supreme condition,
as absolutely necessary, and that in this way a regulative should be
transformed into a constitutive principle. This interchange becomes
evident when I regard this supreme being, which, relatively to the
world, was absolutely (unconditionally) necessary, as a thing per
se. In this case, I find it impossible to represent this necessity
in or by any conception, and it exists merely in my own mind, as the
formal condition of thought, but not as a material and hypostatic
condition of existence.
If you're interested enough to invest quite some time into learning Kant's rather excessive vocabulary, it's worth a read.