Thus I say the conception of a supreme intelligence is a mere idea;that is to say, its objective reality does not consist in the fact that it has an immediate relation to an object (for in this sense we have no means of establishing its objective validity), it is merely a schema constructed according to the necessary conditions of the unity of reason- the schema of a thing in general, which is useful towards the production of the highest degree of systematic unity in the empirical exercise of reason, in which we deduce this or that object of experience from the imaginary object of this idea, as the ground or cause of the said object of experience.In this way, the idea is properly a heuristic, and not an ostensive, conception; it does not give us any information respecting the constitution of an object, it merely indicates how, under the guidance of the idea, we ought to investigate the constitution and the relations of objects in the world of experience.Now, if it can be shown that the three kinds of transcendental ideas (psychological, cosmological, and theological), although not relating directly to any object nor determining it, do nevertheless, on the supposition of the existence of an ideal object, produce systematic unity in the laws of the empirical employment of the reason, and extend our empirical cognition, without ever being inconsistent or in opposition with it-it must be a necessary maxim of reason to regulate its procedure according to these ideas.And this forms the transcendental deduction of all speculative ideas, not as constitutive principles of the extension of our cognition beyond the limits of our experience, but as regulative principles of the systematic unity of empirical cognition, which is by the aid of these ideas arranged and emended within its own proper limits, to an extent unattainable by the operation of the principles of the understanding alone.
I shall make this plainer.Guided by the principles involved in these ideas, we must, in the first place, so connect all the phenomena, actions, and feelings of the mind, as if it were a ****** substance, which, endowed with personal identity, possesses a permanent existence (in this life at least), while its states, among which those of the body are to be included as external conditions, are in continual change.Secondly, in cosmology, we must investigate the conditions of all natural phenomena, internal as well as external, as if they belonged to a chain infinite and without any prime or supreme member, while we do not, on this account, deny the existence of intelligible grounds of these phenomena, although we never employ them to explain phenomena, for the ****** reason that they are not objects of our cognition.Thirdly, in the sphere of theology, we must regard the whole system of possible experience as forming an absolute, but dependent and sensuously-conditioned unity, and at the same time as based upon a sole, supreme, and all-sufficient ground existing apart from the world itself- a ground which is a self-subsistent, primeval and creative reason, in relation to which we so employ our reason in the field of experience, as if all objects drew their origin from that archetype of all reason.In other words, we ought not to deduce the internal phenomena of the mind from a ****** thinking substance, but deduce them from each other under the guidance of the regulative idea of a ****** being; we ought not to deduce the phenomena, order, and unity of the universe from a supreme intelligence, but merely draw from this idea of a supremely wise cause the rules which must guide reason in its connection of causes and effects.
Now there is nothing to hinder us from admitting these ideas to possess an objective and hyperbolic existence, except the cosmological ideas, which lead reason into an antinomy: the psychological and theological ideas are not antinomial.They contain no contradiction;and how, then, can any one dispute their objective reality, since he who denies it knows as little about their possibility as we who affirm? And yet, when we wish to admit the existence of a thing, it is not sufficient to convince ourselves that there is no positive obstacle in the way; for it cannot be allowable to regard mere creations of thought, which transcend, though they do not contradict, all our conceptions, as real and determinate objects, solely upon the authority of a speculative reason striving to compass its own aims.They cannot, therefore, be admitted to be real in themselves; they can only possess a comparative reality- that of a schema of the regulative principle of the systematic unity of all cognition.They are to be regarded not as actual things, but as in some measure analogous to them.We abstract from the object of the idea all the conditions which limit the exercise of our understanding, but which, on the other hand, are the sole conditions of our possessing a determinate conception of any given thing.And thus we cogitate a something, of the real nature of which we have not the least conception, but which we represent to ourselves as standing in a relation to the whole system of phenomena, analogous to that in which phenomena stand to each other.