for some time the path of nature and experience； and discovering
themselves no nearer their object； they suddenly leave this path and
pass into the region of pure possibility； where they hope to reach
upon the wings of ideas what had eluded all their empirical
investigations。 Gaining； as they think； a firm footing after this
immense leap； they extend their determinate conception… into the
possession of which they have e； they know not how… over the
whole sphere of creation； and explain their ideal； which is entirely a
product of pure reason； by illustrations drawn from experience… though
in a degree miserably unworthy of the grandeur of the object； while
they refuse to acknowledge that they have arrived at this cognition or
hypothesis by a very different road from that of experience。
Thus the physico…theological is based upon the cosmological； and
this upon the ontological proof of the existence of a Supreme Being；
and as besides these three there is no other path open to
speculative reason； the ontological proof； on the ground of pure
conceptions of reason； is the only possible one； if any proof of a
proposition so far transcending the empirical exercise of the
understanding is possible at all。
SECTION VII。 Critique of all Theology based upon Speculative
Principles of Reason。
If by the term theology I understand the cognition of a primal
being； that cognition is based either upon reason alone （theologia
rationalis） or upon revelation （theologia revelata）。 The former
cogitates its object either by means of pure transcendental
conceptions； as an ens originarium； realissimum； ens entium； and is
termed transcendental theology； or； by means of a conception derived
from the nature of our own mind； as a supreme intelligence； and must
then be entitled natural theology。 The person who believes in a
transcendental theology alone； is termed a deist； he who
acknowledges the possibility of a natural theology also； a theist。 The
former admits that we can cognize by pure reason alone the existence
of a Supreme Being； but at the same time maintains that our conception
of this being is purely transcendental； and that all we can say of
it is that it possesses all reality； without being able to define it
more closely。 The second asserts that reason is capable of
presenting us； from the analogy with nature； with a more definite
conception of this being； and that its operations； as the cause of all
things； are the results of intelligence and free will。 The former
regards the Supreme Being as the cause of the world… whether by the
necessity of his nature； or as a free agent； is left undetermined； the
latter considers this being as the author of the world。
Transcendental theology aims either at inferring the existence of
a Supreme Being from a general experience； without any closer
reference to the world to which this experience belongs； and in this
case it is called cosmotheology； or it endeavours to cognize the
existence of such a being； through mere conceptions； without the aid
of experience； and is then termed ontotheology。
Natural theology infers the attributes and the existence of an
author of the world； from the constitution of； the order and unity
observable in； the world； in which two modes of causality must be
admitted to exist… those of nature and freedom。 Thus it rises from
this world to a supreme intelligence； either as the principle of all
natural； or of all moral order and perfection。 In the former case it
is termed physico…theology； in the latter； ethical or moral…theology。*
*Not theological ethics； for this science contains ethical laws；
which presuppose the existence of a Supreme Governor of the world；
while moral…theology； on the contrary； is the expression of a
conviction of the existence of a Supreme Being； founded upon ethical
laws。
As we are wont to understand by the term God not merely an eternal
nature； the operations of which are insensate and blind； but a Supreme
Being； who is the free and intelligent author of all things； and as it
is this latter view alone that can be of interest to humanity； we
might； in strict rigour； deny to the deist any belief in God at all；
and regard him merely as a maintainer of the existence of a primal
being or thing… the supreme cause of all other things。 But； as no
one ought to be blamed； merely because he does not feel himself
justified in maintaining a certain opinion； as if he altogether denied
its truth and asserted the opposite； it is more correct… as it is less
harsh… to say； the deist believes in a God； the theist in a living God
（summa intelligentia）。 We shall now proceed to investigate the sources
of all these attempts of reason to establish the existence of a
Supreme Being。
It may be sufficient in this place to define theoretical knowledge
or cognition as knowledge of that which is； and practical knowledge as
knowledge of that which ought to be。 In this view； the theoretical
employment of reason is that by which I cognize a priori （as
necessary） that something is； while the practical is that by which I
cognize a priori what ought to happen。 Now； if it is an indubitably
certain； though at the same time an entirely conditioned truth； that
something is； or ought to happen； either a certain determinate
condition of this truth is absolutely necessary； or such a condition
may be arbitrarily presupposed。 In the former case the condition is
postulated （per thesin）； in the latter supposed （per hypothesin）。
There are certain practical laws… those of morality… which are
absolutely necessary。 Now； if these laws necessarily presuppose the
existence of some being； as the condition of the possibility of
their obligatory power； this being must be postulated； because the
conditioned； from which we reason to this determinate condition； is
itself cognized a priori as absolutely necessary。 We shall at some
future time show that the moral laws not merely presuppose the
existence of a Supreme Being； but also； as themselves absolutely
necessary in a different relation； demand or postulate it… although
only from a practical point of view。 The discussion of this argument
we postpone for the present。
When the question relates merely to that which is； not to that which
ought to be； the conditioned which is presented in experience is
always cogitated as contingent。 For this reason its condition cannot
be regarded as absolutely necessary； but merely as relatively
necessary； or rather as needful； the condition is in itself and a
priori a mere arbitrary presupposition in aid of the cognition； by
reason； of the conditioned。 If； then； we are to possess a
theoretical cognition of the absolute necessity of a thing； we
cannot attain to this cognition otherwise than a priori by means of
conceptions； while it is impossible in this way to cognize the
existence of a cause which bears any relation to an existence given in
experience。
Theoretical cognition is speculative when it relates to an object or
certain conceptions of an object which is not given and cannot be
discovered by means of experience。 It is opposed to the cognition of
nature； which concerns only those objects or predicates which can be
presented in a possible experience。
The principle that everything which happens （the empirically
contingent） must have a cause； is a principle of the cognition of
nature； but not of speculative cognition。 For； if we change it into an
abstract principle； and deprive it of its reference to experience
and the empirical； we shall find that it cannot with justice be
regarded any longer as a synthetical proposition； and that it is
impossible to discover any mode of transition from that which exists
to something entirely different… termed cause。 Nay； more； the
conception of a cause likewise that of the contingent… loses； in
this speculative mode of employing it； all significance； for its
objective reality and meaning are prehensible from experience
alone。
When from the existence of the universe and the things in it the
existence of a cause of the universe is inferred； reason is proceeding
not in the natural； but in the speculative method。 For the principle
of the former enounces； not that things themselves or substances；
but only that which happens or their states… as empirically
contingent； have a cause： the assertion that the existence of
substance itself is contingent is not justified by experience； it is
the assertion of a reason employing its principles in a speculative
manner。 If； again； I infer from the form of the universe； from the way
in which all things are connected and act and react upon each other；
the existence of a cause entirely distinct from the universe… this
would again be a judgement of purely speculative reason； because the
object in this case… the cause… can never be an object of possible
experience。 In both these cases the principle of causality； which is
valid only in the field of experience… useless and even meaningless
beyond this region； would be diverted from its proper destination。
Now I maintain that all attempts of reason to establish a theology
by the aid of speculation alone are fruitless； that the principles
of r