the summum bonum in the world； the possibility of which can
therefore be postulated； and as our reason finds it not conceivable
except on the supposition of a supreme intelligence； the admission
of this existence is therefore connected with the consciousness of our
duty； although the admission itself belongs to the domain of
speculative reason。 Considered in respect of this alone； as a
principle of explanation； it may be called a hypothesis； but in
reference to the intelligibility of an object given us by the moral
law （the summum bonum）； and consequently of a requirement for
practical purposes； it may be called faith； that is to say a pure
rational faith； since pure reason （both in its theoretical and
practical use） is the sole source from which it springs。
From this deduction it is now intelligible why the Greek schools
could never attain the solution of their problem of the practical
possibility of the summum bonum； because they made the rule of the use
which the will of man makes of his freedom the sole and sufficient
ground of this possibility； thinking that they had no need for that
purpose of the existence of God。 No doubt they were so far right
that they established the principle of morals of itself
independently of this postulate； from the relation of reason only to
the will； and consequently made it the supreme practical condition
of the summum bonum； but it was not therefore the whole condition of
its possibility。 The Epicureans had indeed assumed as the supreme
principle of morality a wholly false one； namely that of happiness；
and had substituted for a law a maxim of arbitrary choice according to
every man's inclination； they proceeded； however； consistently
enough in this； that they degraded their summum bonum likewise； just
in proportion to the meanness of their fundamental principle； and
looked for no greater happiness than can be attained by human prudence
（including temperance and moderation of the inclinations）； and this as
we know would be scanty enough and would be very different according
to circumstances； not to mention the exceptions that their maxims must
perpetually admit and which make them incapable of being laws。 The
Stoics； on the contrary； had chosen their supreme practical
principle quite rightly； making virtue the condition of the summum
bonum； but when they represented the degree of virtue required by
its pure law as fully attainable in this life； they not only
strained the moral powers of the man whom they called the wise
beyond all the limits of his nature； and assumed a thing that
contradicts all our knowledge of men； but also and principally they
would not allow the second element of the summum bonum； namely；
happiness； to be properly a special object of human desire； but made
their wise man； like a divinity in his consciousness of the excellence
of his person； wholly independent of nature （as regards his own
contentment）； they exposed him indeed to the evils of life； but made
him not subject to them （at the same time representing him also as
free from moral evil）。 They thus； in fact； left out the second element
of the summum bonum namely； personal happiness； placing it solely in
action and satisfaction with one's own personal worth； thus
including it in the consciousness of being morally minded； in which
they Might have been sufficiently refuted by the voice of their own
nature。
The doctrine of Christianity；* even if we do not yet consider it
as a religious doctrine； gives； touching this point； a conception of
the summum bonum （the kingdom of God）； which alone satisfies the
strictest demand of practical reason。 The moral law is holy
（unyielding） and demands holiness of morals； although all the moral
perfection to which man can attain is still only virtue； that is； a
rightful disposition arising from respect for the law； implying
consciousness of a constant propensity to transgression； or at least a
want of purity； that is； a mixture of many spurious （not moral）
motives of obedience to the law； consequently a self…esteem bined
with humility。 In respect； then； of the holiness which the Christian
law requires； this leaves the creature nothing but a progress in
infinitum； but for that very reason it justifies him in hoping for
an endless duration of his existence。 The worth of a character
perfectly accordant with the moral law is infinite； since the only
restriction on all possible happiness in the judgement of a wise and
all powerful distributor of it is the absence of conformity of
rational beings to their duty。 But the moral law of itself does not
promise any happiness； for according to our conceptions of an order of
nature in general； this is not necessarily connected with obedience to
the law。 Now Christian morality supplies this defect （of the second
indispensable element of the summum bonum） by representing the world
in which rational beings devote themselves with all their soul to
the moral law； as a kingdom of God； in which nature and morality are
brought into a harmony foreign to each of itself； by a holy Author who
makes the derived summum bonum possible。 Holiness of life is
prescribed to them as a rule even in this life； while the welfare
proportioned to it； namely； bliss； is represented as attainable only
in an eternity； because the former must always be the pattern of their
conduct in every state； and progress towards it is already possible
and necessary in this life； while the latter； under the name of
happiness； cannot be attained at all in this world （so far as our
own power is concerned）； and therefore is made simply an object of
hope。 Nevertheless； the Christian principle of morality itself is
not theological （so as to be heteronomy）； but is autonomy of pure
practical reason； since it does not make the knowledge of God and
His will the foundation of these laws； but only of the attainment of
the summum bonum； on condition of following these laws； and it does
not even place the proper spring of this obedience in the desired
results； but solely in the conception of duty； as that of which the
faithful observance alone constitutes the worthiness to obtain those
happy consequences。
*It is monly held that the Christian precept of morality has no
advantage in respect of purity over the moral conceptions of the
Stoics； the distinction between them is； however； very obvious。 The
Stoic system made the consciousness of strength of mind the pivot on
which all moral dispositions should turn； and although its disciples
spoke of duties and even defined them very well； yet they placed the
spring and proper determining principle of the will in an elevation of
the mind above the lower springs of the senses； which owe their
power only to weakness of mind。 With them therefore； virtue was a sort
of heroism in the wise man raising himself above the animal nature
of man； is sufficient for Himself； and； while he prescribes duties
to others； is himself raised above them； and is not subject to any
temptation to transgress the moral law。 All this； however； they
could not have done if they had conceived this law in all its purity
and strictness； as the precept of the Gospel does。 When I give the
name idea to a perfection to which nothing adequate can be given in
experience； it does not follow that the moral ideas are thing
transcendent； that is something of which we could not even determine
the concept adequately； or of which it is uncertain whether there is
any object corresponding to it at all； as is the case with the ideas
of speculative reason； on the contrary； being types of practical
perfection； they serve as the indispensable rule of conduct and
likewise as the standard of parison。 Now if I consider Christian
morals on their philosophical side； then pared with the ideas of
the Greek schools； they would appear as follows： the ideas of the
Cynics； the Epicureans； the Stoics； and the Christians are： simplicity
of nature； prudence； wisdom； and holiness。 In respect of the way of
attaining them； the Greek schools were distinguished from one
another thus that the Cynics only required mon sense； the others
the path of science； but both found the mere use of natural powers
sufficient for the purpose。 Christian morality； because its precept is
framed （as a moral precept must be） so pure and unyielding； takes from
man all confidence that be can be fully adequate to it； at least in
this life； but again sets it up by enabling us to hope that if we
act as well as it is in our power to do； then what is not in our power
will e in to our aid from another source； whether we know how
this may be or not。 Aristotle and Plato differed only as to the origin
of our moral conceptions。
In this manner； the moral laws lead through the conception of the
summum bonum as the object and final end of pure practical reason to
religion； that is； to the recognition of all duties as divine
mands； not as sanctions； that is to say； arbitrary ordinances of
a foreign and contingent in themselves； but as essential laws of every
free will in itself； which； nevertheless； must be regarded as mands
of the Supreme Being； because it is only from a morally perfect
（holy and good） and at the same time all…po